Alerts
Category:GUI manual
Alerts & Reports
Alerts & Reports generate email notifications based on QoS parameters or SIP error conditions. The system includes daily reports, ad hoc reports, and stores all generated items in history.
Overview
The alert system monitors call quality and SIP signaling in real-time, triggering notifications when configured thresholds are exceeded.
Email Configuration Prerequisites
Emails are sent using PHP's mail() function, which relies on the server's Mail Transfer Agent (MTA) such as Exim, Postfix, or Sendmail. Configure your MTA according to your Linux distribution documentation.
Setting the Email "From" Address
To configure the "From" address that appears in outgoing alert emails:
- Navigate to
- GUI > Settings > System Configuration > Email / HTTP Referer
- Locate the field
- DEFAULT_EMAIL_FROM (Default "From" address for outgoing emails)
- Set your desired email address (e.g.,
alerts@yourcompany.com)
This setting applies to all automated emails sent by VoIPmonitor, including:
- QoS alerts (RTP, SIP response, sensors)
- Daily reports
- License notifications
Setting Up the Cron Job
Alert processing requires a cron job that runs every minute:
# Add to /etc/crontab (adjust path based on your GUI installation)
echo "* * * * * root php /var/www/html/php/run.php cron" >> /etc/crontab
# Reload crontab
killall -HUP cron # Debian/Ubuntu
# or
killall -HUP crond # CentOS/RHEL
Configure Alerts
Email alerts can trigger on SIP protocol events or RTP QoS metrics. Access alerts configuration via GUI > Alerts.

Alert Types
RTP Alerts
RTP alerts trigger based on voice quality metrics:
- MOS (Mean Opinion Score) - below threshold
- Packet loss - percentage exceeded
- Jitter - variation exceeded
- Delay (PDV) - latency exceeded
- One-way calls - answered but one RTP stream missing
- Missing RTP - answered but both RTP streams missing
Configure alerts to trigger when:
- Number of incidents exceeds a set value, OR
- Percentage of CDRs exceeds a threshold

RTP&CDR Alerts
RTP&CDR alerts combine RTP quality metrics with CDR-based conditions, including Post Dial Delay (PDD). These alerts are useful for monitoring call setup performance and detecting network latency issues.
Available Conditions:
In the filter-common tab, you can configure conditions including:
- PDD (Post Dial Delay) - Time between sending INVITE and receiving final response. Configure with comparison operators like
PDD > 5(in seconds) to alert on long call setup delays. This can also detect routing loops where looping calls continuously retransmit INVITE without receiving responses (PDD will be very large).
In the base config tab:
- Set the recipient email address for alert notifications
- Consider limiting the max-lines in body to prevent oversized emails when many CDRs match the alert condition
SIP Response Alerts
SIP response alerts trigger based on SIP response codes:
- Empty response field: Matches all call attempts per configured filters
- Response code 0: Matches unreplied INVITE requests (no response received). This is useful for detecting routing loops where calls continuously loop and never receive any SIP response.
- Specific codes: Match exact codes like 404, 503, etc.

Percentage Alerts and the "from all" Checkbox
SIP response alerts can trigger based either on the number of incidents or the percentage of CDRs exceeding a threshold.
When setting a percentage threshold (e.g., >10%):
- "from all" checkbox CHECKED: The percentage is calculated from ALL CDRs in the database (not just those matching filters).
- "from all" checkbox UNCHECKED: The percentage is calculated only from CDRs that match your common filters (IP groups, numbers, etc.). This is the correct setting when monitoring a specific IP group.
Example: Monitor 503 responses for a specific IP group
To alert when the percentage of SIP 503 responses from the "Datora" IP group exceeds 10%:
1. Navigate to GUI > Alerts > filter common subtab 2. In IP/Number Group, select your group (e.g., "Datora") 3. UNCHECK "from all" - this ensures the percentage is calculated only from CDRs involving IPs in the Datora group 4. In the Base config subtab:
* Set Type to SIP Response * Set Response code to503* Set Incidents threshold to>10%
5. Configure recipient emails and save
If you leave "from all" CHECKED, the alert would calculate the 503 percentage across ALL CDRs in your database, which defeats the purpose of monitoring a specific IP group.
Detecting 408 Request Timeout Failures
A 408 Request Timeout response occurs when the caller sends multiple INVITE retransmissions and receives no final response. This is useful for alerting on calls that timeout after the UAS (User Agent Server) sends a provisional response like 100 Trying but then fails to send any further responses.
Use Cases:
- Detect failing PBX or SBC (Session Border Controller) instances that accept calls but stop processing
- Monitor network failures where SIP messages stop flowing after initial dialog establishment
- Identify servers that become unresponsive mid-call setup
Configuration:
1. Navigate to GUI > Alerts
2. Create new alert with type SIP Response
3. Set Response code to 408
4. Optionally add Common Filters (IP addresses, numbers) to narrow scope
5. Save the alert
Understanding the Difference Between Response Code 0 and 408:
- 'Response code 0: Matches calls that received absolutely no response (not even a 100 Trying). These are network or reachability issues.
- Response code 408: Matches calls that received at least one provisional response (like 100 Trying) but eventually timed out. These indicate a server or application layer problem where the UAS stopped responding after initial acknowledgment.
Note: When a call times out with a 408 response, the CDR stores 408 as the Last SIP Response. Alerting on 408 will catch all call setup timeouts, including those where a 100 Trying was initially received.
Sensors Alerts
Sensors alerts monitor the health of VoIPmonitor probes and sniffer instances. This is the most reliable method to check if remote sensors are online and actively monitoring traffic.
Unlike simple network port monitoring (which may show a port as open even if the process is frozen or unresponsive), sensors alerts verify that the sensor instance is actively communicating with the VoIPmonitor GUI server.
- Setup
-
- Configure sensors in Settings > Sensors
- Create a sensors alert to be notified when a probe goes offline or becomes unresponsive
Sensor Health Monitoring Conditions
In addition to detecting offline sensors, you can configure sensors alert conditions to monitor sensor performance issues:
Conditions you can configure:
- Old CDR - Alerts when the sensor has not written CDRs to the database recently. This indicates the sensor is either not capturing calls, or there is a database insertion bottleneck preventing CDRs from being committed.
- Big SQL queue stat - Alerts when the SQL cache queue is growing. The SQL queue represents CDRs waiting in memory to be written to the database. A growing queue indicates the database cannot keep up with write operations.
SQL Queue Threshold Guidance:
The SQL queue is measured in the number of cache files waiting. A healthy sensor should maintain a low SQL count.
- Normal operation: SQL queue should remain near 0 during all traffic conditions.
- Warning level: SQL queue above 20 files indicates a significant delay between packet capture and database insertion.
- Critical level: SQL queue above 100 files indicates severe database performance issues requiring immediate attention.
When configuring a "Big SQL queue stat" alert, setting the threshold to 20 files provides early warning before the problem escalates to critical levels.
Configuring Alert Actions:
When a sensor health alert triggers, you can configure the following actions:
- Email notification - Send alerts to administrators via email.
- External script execution - Execute a custom script with arguments about the triggering sensor and condition. This enables integration with monitoring systems like Nagios or Zabbix, or automated remediation workflows.
The external script receives information about which specific sensor triggered the alert and which health condition was violated, allowing you to build automated responses tailored to the type of failure.
SIP REGISTER RRD Beta Alerts
The SIP REGISTER RRD beta alert type monitors SIP REGISTER response times and alerts when REGISTER packets do not receive a response within a specified threshold (in milliseconds). This is useful for detecting network latency issues, packet loss, or failing switches that cause SIP retransmissions.
This alert serves as an effective proxy to monitor for registration issues, as REGISTER retransmissions often indicate problems with network connectivity or unresponsive SIP servers.
- Configuration
-
- Navigate to GUI > Alerts
- Create a new alert with type SIP REGISTER RRD beta
- Set the response time threshold in milliseconds (e.g., alert if REGISTER does not receive a response within 2000ms)
- Configure recipient email addresses
- Save the alert configuration
The system monitors REGISTER packets and triggers an alert when responses exceed the configured threshold, indicating potential SIP registration failures or network issues.
CDR Trends Alerts
The CDR trends alert type enables trend-based monitoring and alerting on aggregated CDR statistics, including ASR (Answer Seizure Ratio) and other metrics. This alert type compares current performance against historical baselines and triggers notifications when metrics deviate beyond configurable thresholds.
Use Cases:
- Monitor ASR drops or increases over time windows
- Detect sudden changes in call volume patterns
- Compare current hour/day/week against historical data
- Identify quality degradation trends before they become critical
Configuration Parameters:
| Parameter | Description | Example Values |
|---|---|---|
| Type | The metric to monitor for trend changes | ASR (Answer Seizure Ratio), Call count, ACD, etc. |
| Offset | Historical baseline period to compare against | 1 week, 1 day, 1 month |
| Range | Current time window to evaluate | 1 hour, 1 day, 1 week |
| Method | Calculation method for trend comparison | Deviation (detects % change), Threshold (absolute value) |
| Limit Inc./Limit Dec. | Percentage threshold for triggering alerts | 10%, 15%, 20% |
| IP whitelist | Optional filter to limit scope to specific IPs/agents | Source IP addresses or user agents |
Example Configuration - ASR Trend Alert:
To receive an alert when ASR drops by 10% compared to the previous week:
1. Navigate to GUI > Alerts 2. Create new alert with type CDR trends 3. Configure parameters:
- Type: ASR
- Offset: 1 week (compare current period to previous week)
- Range: 1 hour (evaluate hourly)
- Method: Deviation (percentage-based comparison)
- Limit Dec.: 10% (trigger when drop exceeds 10%)
- IP whitelist: (optional) specify specific test user agents or IP addresses
4. Set recipient email addresses 5. Save the alert configuration
How Deviation Method Works:
When using the Deviation method, the system calculates:
Deviation % = ((Current Value - Historical Baseline) / Historical Baseline) * 100
- Limit Inc. triggers when Deviation % > threshold (e.g., ASR increased by 15%)
- Limit Dec. triggers when Deviation % < -threshold (e.g., ASR decreased by 10%)
A 10% ASR drop means current ASR is 90% of the historical baseline.
Understanding Offset vs Range:
- Offset defines the historical reference period (e.g., "1 week" means "same hour last week")
- Range defines the current evaluation window (e.g., "1 hour" means "current hour's ASR")
For example, with Offset=1 week and Range=1 hour, the system compares ASR for "today 09:00-10:00" against "last week 09:00-10:00".
Multiple Register Beta Alerts
The multiple register (beta) alert type detects SIP accounts that are registered from multiple different IP addresses. This is useful for identifying potential security issues, configuration errors, or unauthorized use of SIP credentials.
This alert specifically finds phone numbers or SIP accounts that have registered from more than one distinct IP address within the monitored timeframe.
- Use Cases
-
- Detect SIP account compromise (credential theft leading to registrations from unauthorized IPs)
- Identify configuration issues where phones are registering from multiple networks unexpectedly
- Monitor for roaming behavior when multi-IP registration is not expected
- Audit SIP account usage across distributed environments
- Configuration
-
- Navigate to GUI > Alerts
- Create a new alert with type multiple register (beta)
- Configure recipient email addresses
- Optionally add Common Filters (IP addresses, numbers) to narrow scope - leave filters empty to check ALL SIP numbers/accounts across all customers
- Save the alert configuration
- Alert Scope
-
- With filters: Monitors only the specific IP addresses, numbers, or groups defined in the Common Filters section
- Without filters: Monitors all SIP numbers/accounts across all customers in your system
The alert will trigger whenever it detects a SIP account that has registered from multiple distinct IP addresses, providing details about the affected account(s) and the IP addresses observed.

Common Filters
All alert types support the following filters:
| Filter | Description |
|---|---|
| IP/Number Group | Apply alert to predefined groups (from Groups menu) |
| IP Addresses | Individual IPs or ranges (one per line) |
| Numbers | Individual phone numbers or prefixes (one per line) |
| Email Group | Send alerts to group-defined email addresses |
| Emails | Individual recipient emails (one per line) |
| External script | Path to custom script to execute when alert triggers (see below) |

Using External Scripts for Alert Actions
Beyond email notifications, alerts can execute custom scripts when triggered. This enables integration with third-party systems (webhooks, Datadog, Slack, custom monitoring tools) without sending emails.
Configuration
1. Navigate to GUI > Alerts
2. Create or edit an alert (RTP, SIP Response, Sensors, etc.)
3. In the configuration form, locate the External script field
4. Enter the full path to your custom script (e.g., /usr/local/bin/alert-webhook.sh)
5. Save the alert configuration
The script will execute immediately when the alert triggers.
Script Arguments
The custom script receives alert data as command-line arguments. The format is identical to anti-fraud scripts (see Anti-Fraud Rules):
| Argument | Description |
|---|---|
$1 |
Alert ID (numeric identifier) |
$2 |
Alert name/type |
$3 |
Unix timestamp of alert trigger |
$4 |
JSON-encoded alert data |
Alert Data Structure
The JSON in the fourth argument contains CDR IDs affected by the alert:
{
"cdr": [12345, 12346, 12347],
"alert_type": "MOS below threshold",
"threshold": 3.5,
"actual_value": 2.8
}
Use the cdr array to query additional information from the database if needed.
Example: Send Webhook to Datadog
This bash script sends an alert notification to a Datadog webhook API:
#!/bin/bash
# /usr/local/bin/datadog-alert.sh
# Configuration
WEBHOOK_URL="https://webhook.site/your-custom-url"
DATADOG_API_KEY="your-datadog-api-key"
# Parse arguments
ALERT_ID="$1"
ALERT_NAME="$2"
TIMESTAMP="$3"
ALERT_DATA="$4"
# Convert Unix timestamp to readable date
DATE=$(date -d "@$TIMESTAMP" '+%Y-%m-%d %H:%M:%S')
# Extract relevant data from JSON
cdrCount=$(echo "$ALERT_DATA" | jq -r '.cdr | length')
threshold=$(echo "$ALERT_DATA" | jq -r '.threshold // empty')
actualValue=$(echo "$ALERT_DATA" | jq -r '.actual_value // empty')
# Build webhook payload
PAYLOAD=$(cat <<EOF
{
"alert_id": "$ALERT_ID",
"alert_name": "$ALERT_NAME",
"triggered_at": "$DATE",
"cdr_count": $cdrCount,
"threshold": $threshold,
"actual_value": $actualValue,
"source": "voipmonitor"
}
EOF
)
# Send webhook
curl -X POST "$WEBHOOK_URL" \
-H "Content-Type: application/json" \
-H "Authorization: Bearer $DATADOG_API_KEY" \
-d "$PAYLOAD"
Make the script executable:
chmod +x /usr/local/bin/datadog-alert.sh
Example: Send Slack Notification
#!/bin/bash
# /usr/local/bin/slack-alert.sh
SLACK_WEBHOOK="https://hooks.slack.com/services/YOUR/WEBHOOK/URL"
ALERT_NAME="$2"
ALERT_DATA="$4"
cdrCount=$(echo "$ALERT_DATA" | jq -r '.cdr | length')
curl -X POST "$SLACK_WEBHOOK" \
-H "Content-Type: application/json" \
-d '{
"text": "VoIPmonitor Alert: '"$ALERT_NAME"'",
"attachments": [{
"color": "danger",
"fields": [
{"title": "CDRs affected", "value": "'"$cdrCount"'"}
]
}]
}'
Example: Store Alert Details in File
#!/bin/bash
# /usr/local/bin/log-alert.sh
LOG_DIR="/var/log/voipmonitor-alerts"
mkdir -p "$LOG_DIR"
# Log all arguments for debugging
echo "=== Alert triggered at $(date) ===" >> "$LOG_DIR/alerts.log"
echo "Alert ID: $1" >> "$LOG_DIR/alerts.log"
echo "Alert name: $2" >> "$LOG_DIR/alerts.log"
echo "Timestamp: $3" >> "$LOG_DIR/alerts.log"
echo "Data: $4" >> "$LOG_DIR/alerts.log"
echo "" >> "$LOG_DIR/alerts.log"
Example: Access Source IP Addresses
When querying the CDR database from an alert script, IP addresses are stored as decimal integers in the cdr table. To convert them to human-readable dotted-decimal format (e.g., 185.107.80.4), use either PHP's long2ip() function or MySQL's INET_NTOA() function.
Using PHP's long2ip() (Recommended for Post-Processing)
If you fetch the raw integer value from the database and convert it in your script:
#!/usr/bin/php
<?php
// Parse alert data
$alert = json_decode($argv[4]);
$cdrIds = implode(',', $alert->cdr);
// Query the CDR table - note: sipcallerip is a decimal integer
$query = "SELECT id, sipcallerip, sipcalledip
FROM voipmonitor.cdr
WHERE id IN ($cdrIds)";
$command = "mysql -h MYSQLHOST -u MYSQLUSER -pMYSQLPASS -N -e \"$query\"";
exec($command, $results);
// Process results and convert IP addresses
foreach ($results as $line) {
list($id, $callerIP, $calledIP) = preg_split('/\t/', trim($line));
// Convert decimal integer to dotted-decimal format
$callerIPFormatted = long2ip($callerIP);
$calledIPFormatted = long2ip($calledIP);
echo "CDR ID $id: Caller IP $callerIPFormatted, Called IP $calledIPFormatted\n";
// Example: long2ip(3110817796) returns "185.107.80.4"
}
?>
Using MySQL's INET_NTOA() (Recommended for Database Queries)
If you prefer to handle conversion in the SQL query itself:
#!/usr/bin/php
<?php
// Parse alert data
$alert = json_decode($argv[4]);
$cdrIds = implode(',', $alert->cdr);
// Query with IP conversion done in MySQL
$query = "SELECT id, INET_NTOA(sipcallerip) as caller_ip, INET_NTOA(sipcalledip) as called_ip
FROM voipmonitor.cdr
WHERE id IN ($cdrIds)";
$command = "mysql -h MYSQLHOST -u MYSQLUSER -pMYSQLPASS -N -e \"$query\"";
exec($command, $results);
// Process results - IPs are already formatted
foreach ($results as $line) {
list($id, $callerIP, $calledIP) = preg_split('/\t/', trim($line));
echo "CDR ID $id: Caller IP $callerIP, Called IP $calledIP\n";
}
?>
Common IP Columns in CDR Table
The following columns contain IP addresses (all stored as decimal integers):
| Column | Description |
|---|---|
sipcallerip |
SIP signaling source IP |
sipcalledip |
SIP signaling destination IP |
rtpsrcipX |
RTP source IP for stream X (where X = 0-9) |
rtpdstipX |
RTP destination IP for stream X (where X = 0-9) |
Troubleshooting IP Format Issues
If your alert script receives IP addresses as large numbers (e.g., 3110817796 instead of 185.107.80.4):
1. Verify you are querying the cdr table directly (not using formatted variables)
2. Use long2ip() in PHP or INET_NTOA() in MySQL to convert the value
3. Check that the column is not already being converted by another layer of the application
For reference:
long2ip(3110817796)returns185.107.80.4long2ip(3232255785)returns192.168.1.101long2ip(2130706433)returns127.0.0.1
Important Notes
- IP Address Format: IP addresses in the
cdrtable are stored as decimal integers. Uselong2ip()(PHP) orINET_NTOA()(MySQL) to convert to dotted-decimal format. - Script execution time: The alert processor waits for the script to complete. Keep scripts fast (under 5 seconds) or run them in the background if processing takes longer.
- Script permissions: Ensure the script is executable by the web server user (typically
www-dataorapache). - Error handling: Script failures are logged but do not prevent email alerts from being sent.
- Querying CDRs: The script receives CDR IDs in the JSON data. Query the
cdrtable to retrieve detailed information like caller numbers, call duration, etc. - Security: Validate input before using it in commands or database queries to prevent injection attacks.
Sent Alerts
All triggered alerts are saved in history and can be viewed via GUI > Alerts > Sent Alerts. The content matches what was sent via email.

Parameters Table
The parameters table shows QoS metrics with problematic values highlighted for quick identification.

CDR Records Table
The CDR records table lists all calls that triggered the alert. Each row includes alert flags indicating which thresholds were exceeded:
- (M) - MOS below threshold
- (J) - Jitter exceeded
- (P) - Packet loss exceeded
- (D) - Delay exceeded
Anti-Fraud Alerts
VoIPmonitor includes specialized anti-fraud alert rules for detecting attacks and fraudulent activity. These include:
- Realtime concurrent calls monitoring
- SIP REGISTER flood/attack detection
- SIP PACKETS flood detection
- Country/Continent destination alerts
- CDR/REGISTER country change detection
For detailed configuration of anti-fraud rules and custom action scripts, see Anti-Fraud Rules.
Alerts Based on Custom Reports
In addition to native alert types (RTP, SIP response, Sensors), VoIPmonitor supports generating alerts from custom reports. This workflow enables alerts based on criteria not available in native alert types, such as SIP header values captured via CDR custom headers.
Limitations of Custom Report Alerts
Custom report alerts are designed for filtering by SIP header values captured as CDR custom headers. They have the following limitations:
- No "Group By" functionality for threshold-based alerts: You cannot create an alert that triggers only when multiple events from the same caller ID or called number occur. For example, you cannot configure an alert that triggers when the same caller ID generates multiple SIP 486 responses, while ignoring single isolated failures from different callers.
- Scheduled reports vs. threshold alerts: CDR Summary reports can group data by caller number or called number, but these are scheduled reports that send data on a time-based schedule (e.g., daily), not threshold-based alerts that trigger when specific conditions are met.
- No alert-level aggregation: SIP Response alerts aggregate by total counts or percentages across all calls matching your filters, but cannot aggregate or group by specific caller/called numbers within those filtered results.
Workaround:
The closest available workflow is to create a **CDR Summary daily report** that: 1. Filters by the SIP response code (e.g., 486) 2. Groups by source number (caller) or destination number (called) 3. Sends a scheduled email (e.g., every 15 minutes or hourly)
This report will show which caller numbers have generated failures, but you must manually review the data to identify patterns. The report will be sent on schedule regardless of whether any failures occurred, and there is no way to configure it to only trigger when a specific threshold per unique caller is exceeded.
Feature Request:
Alerting based on grouped thresholds (e.g., "alert if the same caller ID generates >X SIP 486 responses") is a requested feature not currently available in VoIPmonitor. If you require this functionality, submit a feature request describing your specific use case.
Workflow Overview =
1. Capture custom SIP headers in the database 2. Create a custom report filtered by the custom header values 3. Generate an alert from that report 4. Configure alert email options (e.g., limit email size)
Example: Alert on SIP Max-Forwards Header Value =
This example shows how to receive an alert when the SIP Max-Forwards header value drops below 15.
Step 1: Configure Sniffer Capture
Add the header to your /etc/voipmonitor.conf configuration file:
# Capture Max-Forwards header
custom_headers = Max-Forwards
Restart the sniffer to apply changes:
service voipmonitor restart
Step 2: Configure Custom Header in GUI
1. Navigate to GUI > Settings > CDR Custom Headers
2. Select Max-Forwards from the available headers
3. Enable Show as Column to display it in CDR views
4. Save configuration
Step 3: Create Custom Report
1. Navigate to GUI > CDR Custom Headers or use the Report Generator
2. Create a filter for calls where Max-Forwards is less than 15
3. Since custom headers store string values, use a filter expression that matches the desired values:
15 14 13 12 11 10 0_ _
Include additional space-separated values or use NULL to match other ranges as needed.
4. Run the report to verify it captures the expected calls
Step 4: Generate Alert from Report
You can create an alert based on this custom report using the Daily Reports feature:
1. Navigate to GUI > Reports > Configure Daily Reports 2. Click Add Daily Report 3. Configure the filter to target the custom header criteria (e.g., Max-Forwards < 15) 4. Set the schedule (e.g., run every hour) 5. Save the daily report configuration
Step 5: Limit Alert Email Size (Optional)
If the custom report generates many matching calls, the alert email can become large. To limit the email size:
1. Edit the daily report 2. Go to the Basic Data tab 3. Set the max-lines in body option to the desired limit (e.g., 100 lines)
Additional Use Cases =
This workflow can be used for various custom monitoring scenarios:
- SIP headers beyond standard SIP response codes - Monitor any custom SIP header
- Complex filtering logic - Create reports based on multiple custom header filters
- Threshold monitoring for string fields - When numeric comparison is not available, use string matching
For more information on configuring custom headers, see CDR Custom Headers.
Troubleshooting Email Alerts
If email alerts are not being sent, the issue is typically with the Mail Transfer Agent (MTA) rather than VoIPmonitor.
Step 1: Test Email Delivery from Command Line
Before investigating complex issues, verify your server can send emails:
# Test using the 'mail' command
echo "Test email body" | mail -s "Test Subject" your.email@example.com
If this fails, the issue is with your MTA configuration, not VoIPmonitor.
Step 2: Check MTA Service Status
Ensure the MTA service is running:
# For Postfix (most common)
sudo systemctl status postfix
# For Exim (Debian default)
sudo systemctl status exim4
# For Sendmail
sudo systemctl status sendmail
If the service is not running or not installed, install and configure it according to your Linux distribution's documentation.
Step 3: Check Mail Logs
Examine the MTA logs for specific error messages:
# Debian/Ubuntu
tail -f /var/log/mail.log
# RHEL/CentOS/AlmaLinux/Rocky
tail -f /var/log/maillog
Common errors and their meanings:
| Error Message | Cause | Solution |
|---|---|---|
| Connection refused | MTA not running or firewall blocking | Start MTA service, check firewall rules |
| Relay access denied | SMTP relay misconfiguration | See "Configuring SMTP Relay" below |
| Authentication failed | Incorrect credentials | Verify credentials in sasl_passwd |
| Host or domain name lookup failed | DNS issues | Check /etc/resolv.conf |
| Greylisted | Temporary rejection | Wait and retry, or whitelist sender |
Step 4: Check Mail Queue
Emails may be stuck in the queue if delivery is failing:
# View the mail queue
mailq
# Force immediate delivery attempt
postqueue -f
Deferred or failed messages in the queue contain error details explaining why delivery failed.
= Configuring SMTP Relay
If you encounter "Relay access denied" errors, your Postfix server cannot send emails through your external SMTP server. There are two solutions:
Solution 1: Configure External SMTP to Permit Relaying (Recommended for Trusted Networks)
If the VoIPmonitor server is in a trusted network, configure your external SMTP server to permit relaying from the VoIPmonitor server's IP address:
1. Access your external SMTP server configuration
2. Add the VoIPmonitor server's IP address to the allowed relay hosts (mynetworks)
3. Save configuration and reload: postfix reload
Solution 2: Configure Postfix SMTP Authentication (Recommended for Remote SMTP)
If using an external SMTP server that requires authentication, configure Postfix to authenticate using SASL:
1. Install SASL authentication packages:
# Debian/Ubuntu
sudo apt-get install libsasl2-modules
# RHEL/CentOS/AlmaLinux/Rocky
sudo yum install cyrus-sasl-plain
2. Configure Postfix to use the external SMTP relay:
Edit /etc/postfix/main.cf:
# Use external SMTP as relay host
relayhost = smtp.yourprovider.com:587
# Enable SASL authentication
smtp_sasl_auth_enable = yes
# Use SASL password file
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
# Disable anonymous authentication (use only SASL)
smtp_sasl_security_options = noanonymous
# Enable TLS (recommended)
smtp_tls_security_level = encrypt
3. Create the SASL password file with your SMTP credentials:
# Create the file (your SMTP username and password)
echo "[smtp.yourprovider.com]:587 username:password" | sudo tee /etc/postfix/sasl_passwd
# Secure the file (rw root only)
sudo chmod 600 /etc/postfix/sasl_passwd
# Create the Postfix hash database
sudo postmap /etc/postfix/sasl_passwd
# Reload Postfix
sudo systemctl reload postfix
4. Test email delivery:
echo "Test email" | mail -s "SMTP Relay Test" your.email@example.com
If successful, emails should be delivered through the authenticated SMTP relay.
Step 5: Verify Cronjob
Ensure the alert processing script runs every minute:
# Check current crontab
crontab -l
You should see:
* * * * * root php /var/www/html/php/run.php cron
If missing, add it:
crontab -e
# Add the line above, then reload cron
killall -HUP cron
Step 6: Verify Alert Configuration in GUI
After confirming the MTA works:
- Navigate to GUI > Alerts
- Verify alert conditions are enabled
- Check that recipient email addresses are valid
- Go to GUI > Alerts > Sent Alerts to see if alerts were triggered
Diagnosis:
- Entries in "Sent Alerts" but no emails received → MTA issue
- No entries in "Sent Alerts" → Check alert conditions or cronjob
Step 7: Test PHP mail() Function
Isolate the issue by testing PHP directly:
php -r "mail('your.email@example.com', 'Test from PHP', 'This is a test email');"
- If this works but VoIPmonitor alerts don't → Check GUI cronjob and alert configuration
- If this fails → MTA or PHP configuration issue
Troubleshooting Concurrent Calls Alerts Not Triggering
CDR-based concurrent calls alerts may not trigger as expected due to database queue delays or alert timing configuration. Unlike realtime concurrent calls alerts (see Anti-Fraud Rules), CDR-based alerts require CDRs to be written to the database before evaluation.
Check SQL Cache Files Queue
A growing SQL cache queue can prevent CDR-based alerts from triggering because the alert processor evaluates CDRs that have already been stored in the database, not calls still waiting in the queue.
- Navigate to GUI > Settings > Sensors
- Check the RRD chart for SQL cache files (SQLq/SQLf metric)
- If the queue is growing during peak times:
- Database cannot keep up with CDR insertion rates
- Alerts evaluate outdated data because recent CDRs have not been written yet
- See Delay between active call and cdr view for solutions
CDR Timing vs "CDR not older than" Setting
CDR-based alerts include a CDR not older than parameter that filters which CDRs are considered for alert evaluation.
- Parameter location: In the concurrent calls alert configuration form
- Function: Only CDRs newer than this time window are evaluated
- Diagnosis:
- Verify that the time difference between Last CDR in database and Last CDR in processing queue (in Sensors status) is smaller than your CDR not older than value
- If the delay is larger, CDRs are being excluded from alert evaluation
- Common causes: Database overload, slow storage, insufficient MySQL configuration
- Solution:
- Increase the CDR not older than value to match your database performance
- See SQL_queue_is_growing_in_a_peaktime and Scaling for database tuning
- Check SQLq value should remain low (under 1000) during peak load
"Check Interval" Parameter and Low Thresholds
When testing concurrent calls alerts with very low thresholds (e.g., greater than 0 calls or 1 call), consider the Check interval parameter.
- Parameter location: In the concurrent calls alert configuration form
- Function: How often the alert condition is evaluated (time window for concurrent call calculation)
- Issue with low thresholds:**
- A call lasting 300 seconds (5 minutes) will show as concurrent for the entire duration
- If Check interval is shorter than typical call durations, you may see temporary concurrent counts that disappear between evaluations
- Recommendation for testing:**
- Increase the Check interval to a longer duration (e.g., 60 minutes) when testing with very low thresholds
- This ensures concurrent calls are counted over a longer time window, avoiding false negatives from short interval checks
Fraud Concurrent Calls vs Regular Concurrent Calls Alerts
VoIPmonitor provides two different alert types for concurrent calls monitoring, which operate on different data sources and have different capabilities:
| Feature | Fraud Concurrent Calls | Regular Concurrent Calls |
|---|---|---|
| Data source | SIP INVITEs (realtime) | CDRs (after call ends) |
| Processing type | Realtime (packet inspection) | CDR-based (database query) |
| Aggregation ("BY" dropdown) | Source IP only (hard-coded) | Source IP, Destination IP, Domain, Custom Headers |
| Domain filtering | Not available (major limitation) | Available via SQL filter |
| Timing | Immediate (no database delay) | Delayed (requires CDR insertion) |
| Where configured | GUI > Alerts > Anti Fraud | GUI > Alerts |
| Table name | Standard alerts table |
Key Differences:
- Fraud concurrent calls detect concurrent INVITEs in realtime but the "BY" dropdown only supports Source IP aggregation. This is a hard-coded limitation of the realtime detection logic designed for detecting attacks from specific IPs. Use this for attack detection where you need immediate alerts.
- Regular concurrent calls alerts use stored CDRs and support multiple aggregation options including Destination IP (Called), Source IP, Domain, and custom headers via the Common Filters tab. Use this for capacity planning, trunk/capacity monitoring, or when you need to filter by destination.
- Destination IP monitoring: If you need to alert when concurrent calls to a specific destination IP (e.g., carrier, trunk) exceed a threshold, use the regular Concurrent calls alert. The Fraud concurrent calls alert cannot filter or aggregate by destination IP.
Example use cases:
| Scenario | Recommended Alert Type | Configuration |
|---|---|---|
| Detect flooding/attack from specific source IP (immediate) | Fraud: realtime concurrent calls | GUI > Alerts > Anti Fraud, BY: Source IP |
| Monitor trunk capacity limit (destination IP threshold) | Concurrent calls | GUI > Alerts, BY: Destination IP (Called) |
| Detect domain-specific concurrent call patterns | Concurrent calls | GUI > Alerts, Common Filters: Domain |
| Detect attacks with immediate triggering | Fraud: realtime concurrent calls | GUI > Alerts > Anti Fraud |
If you have configured a concurrent calls alert and need filtering by destination IP, domain, or custom headers, verify that you are using the regular Concurrent calls alert in GUI > Alerts and not the fraud variant.
Troubleshooting Alerts Not Triggering (General)
If alerts are not appearing in the Sent Alerts history at all, the problem is typically with the alert processor not evaluating alerts. This is different from MTA issues where alerts appear in history but emails are not sent.
Enable Detailed Alert Processing Logs
To debug why alerts are not being evaluated, enable detailed logging for the alert processor by adding the following line to your GUI configuration file:
# Edit the config file (adjust path based on your GUI installation)
nano ./config/system_configuration.php
Add this line at the end of the file:
<?php
define('CRON_LOG_FILE', '/tmp/alert.log');
?>
This enables logging that shows which alerts are being processed during each cron job run.
Increase Parallel Processing Threads
If you have many alerts or reports, the default number of parallel threads may cause timeout issues. Increase the parallel task limit:
# Edit the configuration file
nano ./config/configuration.php
Add this line at the end of the file:
<?php
define('CRON_PARALLEL_TASKS', 8);
?>
The value of 8 is recommended for high-load environments. Adjust based on your alert/report volume and server capacity.
Monitor Alert Processing Logs
After enabling logging, monitor the alert log file to see which alerts are being processed:
# Watch the log in real-time
tail -f /tmp/alert.log
The log shows entries like:
begin alert [alert_name]
end alert [alert_name]
Interpreting the logs:
- If you do not see your alert name in the logs → The alert processor is not evaluating it. Check your alert configuration, filters, and data availability.
- If you see the alert in logs but it does not trigger → The alert conditions are not being met. Check your thresholds, filter logic, and verify the CDR data matches your expectations.
- If logs are completely empty → The cron job may not be running or the GUI configuration files are not being loaded. Verify the cron job and file paths.
Alert Not Appearing in Logs
If your alert does not appear in `/tmp/alert.log`:
1. Verify the cron job is running:
# Check the cron job exists
crontab -l
# Manually test the cron script to see errors
php ./php/run.php cron
2. Verify data exists in CDR:
# Check if the calls that should trigger the alert exist
# Navigate to GUI > CDR > Browse and filter for the timeframe
3. Check alert configuration:
- Verify alert is enabled
- Verify filter logic matches your data (IP addresses, numbers, groups)
- Verify thresholds are reasonable for the actual QoS metrics
- Verify GUI license is not locked (Check GUI > Settings > License)
"Crontab Log is Too Old" Warning - Database Performance Issues
The VoIPmonitor GUI displays a warning message "Crontab log is too old" when the last successful cron run timestamp exceeds the expected interval. While this often indicates a missing or misconfigured cron job, it can also occur when the database is overloaded and the cron script runs slowly.
Common Causes
- Missing or broken cron entry - The cron job does not exist in /etc/crontab or the command fails when executed
- Database overload - The cron job runs but completes slowly due to database performance bottlenecks, causing the "last run" timestamp to drift outside the expected window
Distinguishing the Causes
Use the following diagnostic workflow to determine if the issue is cron configuration vs. database performance:
Step 1: Verify the cron job is actually running
Check if the cron execution timestamp is updating (even if slowly):
# Check the current cron timestamp from the database
mysql -u voipmonitor -p voipmonitor -e "SELECT name, last_run FROM scheduler LIMIT 1"
# The last_run timestamp should update at least every few minutes
# If it never updates, the cron is not running (see Step 2)
# If it updates but lags by more than 5-10 minutes, it's a performance issue (see Step 3)
Step 2: If cron is not running at all
Follow the standard cron setup instructions in the "Setting Up the Cron Job" section above. Common issues:
- Cron entry missing from /etc/crontab
- Incorrect PHP path (use full path like /usr/bin/php instead of php)
- PHP CLI missing IonCube loader (check with `php -r 'echo extension_loaded("ionCube Loader")?"yes":"no";'`)
- Wrong file permissions or incorrect web directory path
- PHP CLI version mismatch - System CLI PHP differs from web server PHP
PHP CLI Version Mismatch Fix
Even if the cron job exists and IonCube Loader is installed for both web and CLI, the CLI may be using a different PHP version than the web server, causing the cron script to fail. This commonly occurs when multiple PHP versions are installed on the system.
Symptoms:
- Cron job exists in /etc/crontab
- PHP CLI has IonCube loader installed
- The GUI shows "Crontab log is too old" warning
- Manual command execution succeeds when using the correct PHP version
Diagnosis:
1. Check the target PHP version required by the GUI:
cat /var/www/html/ioncube_phpver
# Output may be: 81 (for PHP 8.1), 82 (for PHP 8.2), etc.
2. Check the current CLI PHP version:
php -v
# Example output: PHP 8.2.26 (the default CLI version may not match the GUI requirement)
3. List available PHP CLI versions:
ls /usr/bin/php*
# You may see: php8.1, php8.2, php8.3
Solution: Set CLI PHP Version to Match Web Server
Use the `update-alternatives` command to set the default CLI PHP version to match the web server:
# If ioncube_phpver shows "81", set CLI to PHP 8.1
sudo update-alternatives --set php /usr/bin/php8.1
# If ioncube_phpver shows "82", set CLI to PHP 8.2
sudo update-alternatives --set php /usr/bin/php8.2
# Verify the change
php -v
which php
# Should now point to the correct version
Verify the Fix:
Test the cron command manually and check IonCube is loaded with the new version:
cd /var/www/html
php php/run.php cron
# Verify IonCube is loaded
php -r 'echo extension_loaded("ionCube Loader")?"yes":"no";'
# Should output: yes
After a few minutes, the "Crontab log is too old" warning in the GUI should disappear, confirming the cron job is now running successfully.
Step 3: If cron runs but slowly (database performance issue)
When the cron job runs but takes a long time to complete, the issue is database overload. Diagnose using the Sensors statistics:
- Navigate to GUI > Settings > Sensors
- Click on the sensor status to view detailed statistics
- Compare the following timestamps:
- Last CDR in database** - The timestamp of the most recently completed call stored in MySQL
- Last CDR in processing queue** - The timestamp of the most recent call reached by the sniffer
If there is a significant delay (minutes or more) between these two timestamps during peak traffic, the database cannot keep up with CDR insertion. This causes alert/reports processing (run.php cron) to also run slowly.
Solutions for Database Performance Issues
- 1. Check MySQL configuration**
Ensure your MySQL/MariaDB configuration follows the recommended settings for your call volume. Key parameters:
innodb_flush_log_at_trx_commit- Set to 2 for better performance (or 0 in extreme high-CPS environments)innodb_buffer_pool_size- Allocate 70-80% of available RAM for high-volume deploymentsinnodb_io_capacity- Match your storage system capabilities (e.g., 1000000 for NVMe SSDs)
See Scaling and High-Performance_VoIPmonitor_and_MySQL_Setup_Manual for detailed tuning guides.
- 2. Increase database write threads**
In /etc/voipmonitor.conf, increase the number of threads used for writing CDRs:
mysqlstore_max_threads_cdr = 8 # Default is 4, increase based on workload
- 3. Monitor SQL queue statistics**
In the expanded status view (GUI > Settings > Sensors > status), check the SQLq value:
- SQLq (SQL queue) growing steadily - Database is a bottleneck, calls are waiting in memory
- SQLq remains low (under 1000) - Database is keeping up, may need other tuning
See SQL_queue_is_growing_in_a_peaktime for more information.
- 4. Reduce alert/report processing load**
Too many alert rules or complex reports can exacerbate the problem:
- Review and disable unnecessary alerts in GUI > Alerts
- Reduce the frequency of daily reports (edit in GUI > Reports)
- Increase parallel processing tasks: In
/var/www/html/configuration.php, setdefine('CRON_PARALLEL_TASKS', 8);(requires increasing PHP memory limits)
- 5. Check database query performance**
Identify slow queries:
# Enable slow query logging in my.cnf
slow_query_log = 1
long_query_time = 2
# After waiting for a cron cycle, check the slow query log
tail -f /var/log/mysql/slow.log
Look for queries taking more than a few seconds. Common culprits:
- Missing indexes on frequently filtered columns (caller, callee, sipcallerip, etc.)
- Complex alert conditions joining large tables
- Daily reports scanning millions of rows without date range limitations
- 6. Scale database architecture**
For very high call volumes (4000+ concurrent calls), consider:
- Separate database server from sensor hosts
- Use MariaDB with LZ4 page compression
- Implement database replication for read queries
- Use hourly table partitioning for improved write performance
See High-Performance_VoIPmonitor_and_MySQL_Setup_Manual for architecture recommendations.
Verification
After applying fixes:
1. Monitor the "Crontab log is too old" timestamp in the GUI
* The timestamp should update every 1-3 minutes during normal operation * If it still lags by 10+ minutes, further tuning is required
2. Check sensor statistics (GUI > Settings > Sensors)
* The delay between "Last CDR in database" and "Last CDR in processing queue" should be under 1-2 minutes during peak load * SQLq should remain below 1000 and not grow continuously
3. Test alert processing manually
# Run the cron script manually and measure execution time
time php /var/www/html/php/run.php cron
# Should complete within 10-30 seconds in most environments
# If it takes longer than 60-120 seconds, database tuning is needed
See Also
- Anti-Fraud Rules - Detailed fraud detection configuration
- Reports - Daily reports and report generator
- Sniffer Troubleshooting - General troubleshooting
AI Summary for RAG
Summary: VoIPmonitor Alerts & Reports system for email notifications on QoS and SIP issues. Covers RTP alerts (MOS, jitter, packet loss), SIP response alerts (including detecting 408 Request Timeout from 100 Trying scenarios), sensors health monitoring, SIP REGISTER RRD beta alerts for monitoring registration response times, multiple register (beta) alerts for detecting SIP accounts registered from multiple IP addresses (useful for detecting credential theft or unauthorized access), RPT&CDR alerts for Post Dial Delay (PDD) monitoring with filter-common tab conditions (e.g., PDD > 5 in seconds) and base config tab for email recipient and max-lines in body settings, creating alerts from custom reports based on CDR custom headers, and CDR trends alerts for trend-based monitoring and alerting on aggregated CDR statistics including ASR (Answer Seizure Ratio). CDR trends include configuration parameters: Type (ASR, call count, ACD), Offset (historical baseline: 1 week/day/month), Range (current window: 1 hour/day/week), Method (Deviation for percentage change or Threshold for absolute value), Limit Inc./Limit Dec. (percentage threshold for triggering alerts), and IP whitelist (optional filter for specific IPs/agents). Example: Set Type=ASR, Offset=1 week, Range=1 hour, Method=Deviation, Limit Dec.=10% to alert when ASR drops by 10% compared to same hour last week. PERCENTAGE ALERTS CRITICAL: When setting percentage thresholds like >10%, the "from all" checkbox controls the calculation base: CHECKED calculates from ALL CDRs in database, UNCHECKED calculates only from CDRs matching common filters (IP groups, numbers). Always UNCHECK "from all" when monitoring specific IP groups. Includes email troubleshooting for MTA configuration, setting the "From" address for outbound emails (GUI > Settings > System Configuration > Email / HTTP Referer > DEFAULT_EMAIL_FROM field), detailed debugging for alerts not triggering using CRON_LOG_FILE and CRON_PARALLEL_TASKS, external scripts for webhook integration (Datadog, Slack, third-party monitoring), and accessing source IP addresses from alert scripts with proper decimal-to-dotted-decimal conversion using PHP's long2ip() or MySQL's INET_NTOA(). TROUBLESHOOTING concurrent calls alerts: CDR-based alerts may not trigger due to SQL queue delays (check SQL cache files RRD chart in GUI > Settings > Sensors), verify "CDR not older than" parameter is larger than delay between "Last CDR in database" and "Last CDR in processing queue", increase "Check interval" for low threshold testing (e.g., >0 calls use 60 minutes), and understand fraud concurrent calls vs regular concurrent calls: fraud uses INVITEs realtime but lacks domain filtering, regular uses CDRs with domain support but has database delay.
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Key Questions:
- How do I configure a percentage alert for IP groups?
- What does the "from all" checkbox do in alerts?
- How do I trigger an alert when percentage of 503 responses exceeds threshold for a specific IP group?
- How do I set percentage thresholds like >10% in alerts?
- Should the "from all" checkbox be checked when monitoring a specific IP group?
- How do I configure alerts based on ASR trend changes?
- How do I create an alert for a 10% ASR drop over the last hour?
- What is the CDR trends alert type?
- How do I use CDR trends for trend-based monitoring?
- How do I configure Offset and Range parameters in CDR trends alerts?
- What is the Deviation method in CDR trends alerts?
- How do I set Limit Inc and Limit Dec for trend alerts?
- How do I compare current ASR to previous week in alerts?
- How do I detect ASR drops or increases over time windows?
- What is the IP whitelist in CDR trends alerts?
- How do I create an alert for Answer Seizure Ratio trends?
- What is the difference between Offset and Range in trend alerts?
- How do I monitor call volume pattern changes with alerts?
- How do I use trend-based alerts for quality degradation detection?
- How do I create an email alert for high Post Dial Delay (PDD)?
- How do I configure the "From" address for alert emails?
- Where do I set the email from header in VoIPmonitor?
- How do I set up email alerts in VoIPmonitor?
- What types of alerts are available (RTP, SIP, Sensors, REGISTER RRD beta, multiple register beta)?
- How do I detect calls with 408 Request Timeout after 100 Trying?
- How do I create an alert for calls where 100 Trying is sent but no further response?
- What is the difference between response code 0 and 408?
- How do I monitor and alert on SIP REGISTER retransmissions?
- How do I detect registration response time issues?
- How can I use SIP REGISTER RRD beta alert for detecting switch problems?
- How do I detect SIP accounts registered from multiple IP addresses?
- How do I use multiple register (beta) alert to find accounts with multiple IP registrations?
- How do I configure multiple register (beta) alert to check all SIP numbers across all customers?
- How do I detect SIP account compromise or credential theft using alerts?
- How do I monitor for unauthorized SIP account usage?
- How do I configure crontab for alert processing?
- How do I monitor remote sensor health?
- Why are email alerts not being sent?
- How do I troubleshoot MTA email issues?
- How can I create alerts based on SIP headers like Max-Forwards?
- How do I use CDR custom headers for custom reports?
- How do I limit the size of alert emails from custom reports?
- Why are alerts not triggering or appearing in Sent Alerts?
- How do I enable detailed alert processing logs using CRON_LOG_FILE?
- How do I increase parallel alert processing threads with CRON_PARALLEL_TASKS?
- How do I monitor /tmp/alert.log for alert processing debug information?
- How do I configure external scripts for alerts?
- How do I send webhooks from VoIPmonitor alerts to Datadog?
- How do I send alerts to Slack from VoIPmonitor?
- What command-line arguments are passed to alert scripts?
- What JSON data structure is provided to external scripts?
- How do I access source IP addresses from alert scripts?
- Why are IP addresses in alert scripts showing as decimal numbers?
- How do I convert decimal IP addresses to human-readable format?
- What is long2ip() in PHP and how do I use it for IP addresses?
- What is INET_NTOA() in MySQL and how do I use it for IP conversion?
- How do I access sipcallerip, sipcalledip, rtpsrcip from alert scripts?
- How do I convert 3110817796 to 185.107.80.4 in an alert script?
- Why are concurrent calls alerts not triggering?
- How do I check SQL queue for alert timing issues?
- What is the "CDR not older than" parameter in concurrent calls alerts?
- How do I verify if database delays are preventing alerts from triggering?
- How do I monitor SQL cache files queue in GUI > Settings > Sensors?
- What is the "Check interval" parameter in concurrent calls alerts?
- How should I configure "Check interval" for low threshold testing (e.g., >0 calls)?
- What is the difference between fraud concurrent calls and regular concurrent calls alerts?
- Can fraud concurrent calls filter by domain in SIP headers?
- Do regular concurrent calls alerts support domain filtering?
- Why is my domain-based concurrent calls alert not working?
- What is SQLq/SQLf in the Sensors status?
- How does "Last CDR in database" vs "Last CDR in processing queue" affect alerts?
- What should the SQL queue value be during peak load?
- What does "Crontab log is too old" warning mean?
- Why does the cron job exist but fail to execute?
- How do I fix PHP CLI version mismatch for cron jobs?
- How do I check what PHP version the web server is using?
- What is the ioncube_phpver file?
- How do I use update-alternatives to set the CLI PHP version?
- How do I set default PHP CLI version to match the web server?
- How do I verify if IonCube Loader is loaded in PHP CLI?
- Why does the cron job fail even with IonCube installed?