Proxmox VE Webhook Notifications: Slack, Discord, and Telegram Alerts

Proxmox VE 8 Notification System

Proxmox VE 8 introduced a modern notification framework that replaces the legacy email-only approach. The new system supports multiple notification endpoints (SMTP, Gotify, webhooks) and uses matchers to route specific events to specific targets. This means you can send backup completion notices to email, HA failover alerts to Slack, and critical errors to a Telegram group — all from the built-in notification system.

Webhook Notifications with curl

While Proxmox VE 8 has a built-in webhook endpoint type, you can also use hook scripts for maximum flexibility. The most common approach is using curl to POST to messaging platform webhooks.

Slack Notifications

Create a Slack incoming webhook in your Slack workspace (Apps > Incoming Webhooks), then create a notification script:

# Create the Slack notification script:
cat > /usr/local/bin/notify-slack.sh << 'SCRIPT'
#!/bin/bash
SLACK_WEBHOOK="https://hooks.slack.com/services/YOUR/WEBHOOK/URL"
MESSAGE="$1"
SEVERITY="${2:-info}"

# Color based on severity:
case $SEVERITY in
    error)   COLOR="#ff0000" ;;
    warning) COLOR="#ffaa00" ;;
    *)       COLOR="#36a64f" ;;
esac

curl -s -X POST "$SLACK_WEBHOOK" \
  -H 'Content-Type: application/json' \
  -d "{
    \"attachments\": [{
      \"color\": \"$COLOR\",
      \"title\": \"Proxmox Alert - $(hostname)\",
      \"text\": \"$MESSAGE\",
      \"ts\": $(date +%s)
    }]
  }"
SCRIPT

chmod +x /usr/local/bin/notify-slack.sh

# Test it:
/usr/local/bin/notify-slack.sh "Test notification from Proxmox" "info"

Discord Notifications

Discord webhooks are similar to Slack. Create a webhook in your Discord channel (Channel Settings > Integrations > Webhooks):

# Create the Discord notification script:
cat > /usr/local/bin/notify-discord.sh << 'SCRIPT'
#!/bin/bash
DISCORD_WEBHOOK="https://discord.com/api/webhooks/YOUR/WEBHOOK/URL"
MESSAGE="$1"
SEVERITY="${2:-info}"

case $SEVERITY in
    error)   COLOR=16711680 ;;   # Red
    warning) COLOR=16744448 ;;   # Orange
    *)       COLOR=3584611 ;;    # Green
esac

curl -s -X POST "$DISCORD_WEBHOOK" \
  -H 'Content-Type: application/json' \
  -d "{
    \"embeds\": [{
      \"title\": \"Proxmox Alert - $(hostname)\",
      \"description\": \"$MESSAGE\",
      \"color\": $COLOR,
      \"timestamp\": \"$(date -u +%Y-%m-%dT%H:%M:%SZ)\"
    }]
  }"
SCRIPT

chmod +x /usr/local/bin/notify-discord.sh

Telegram Notifications

Create a Telegram bot via BotFather, get the bot token and chat ID, then:

# Create the Telegram notification script:
cat > /usr/local/bin/notify-telegram.sh << 'SCRIPT'
#!/bin/bash
BOT_TOKEN="YOUR_BOT_TOKEN"
CHAT_ID="YOUR_CHAT_ID"
MESSAGE="$1"

curl -s -X POST "https://api.telegram.org/bot${BOT_TOKEN}/sendMessage" \
  -d "chat_id=${CHAT_ID}" \
  -d "parse_mode=HTML" \
  -d "text=Proxmox Alert - $(hostname)%0A${MESSAGE}"
SCRIPT

chmod +x /usr/local/bin/notify-telegram.sh

# Find your chat ID (send a message to your bot first, then):
curl -s "https://api.telegram.org/botYOUR_BOT_TOKEN/getUpdates" | python3 -m json.tool | grep chat -A5

Backup Completion Hooks

Proxmox calls hook scripts at various stages of the backup process. Create a vzdump hook script to send notifications on backup completion or failure:

# Create the backup hook script:
cat > /usr/local/bin/vzdump-hook.sh << 'SCRIPT'
#!/bin/bash
# vzdump hook script - called with: phase, mode, vmid
PHASE="$1"
MODE="$2"
VMID="$3"

case "$PHASE" in
    job-end)
        /usr/local/bin/notify-slack.sh "Backup job completed successfully for VM $VMID (mode: $MODE)" "info"
        ;;
    job-abort)
        /usr/local/bin/notify-slack.sh "BACKUP FAILED for VM $VMID (mode: $MODE)" "error"
        ;;
    backup-end)
        /usr/local/bin/notify-slack.sh "Backup completed: VM $VMID" "info"
        ;;
    log-end)
        /usr/local/bin/notify-slack.sh "Backup log finalized: VM $VMID" "info"
        ;;
esac
SCRIPT

chmod +x /usr/local/bin/vzdump-hook.sh

# Configure vzdump to use the hook:
# In /etc/vzdump.conf:
echo "script: /usr/local/bin/vzdump-hook.sh" >> /etc/vzdump.conf

# Or per-job via the web UI: Datacenter > Backup > Edit > Advanced > Hook Script

HA Failover Alerts

Monitor HA failover events by watching the HA manager log:

# Create an HA monitoring script:
cat > /usr/local/bin/ha-monitor.sh << 'SCRIPT'
#!/bin/bash
# Check for recent HA failover events
LAST_CHECK="/tmp/ha-monitor-last"
LOG="/var/log/pve/ha-manager.log"

if [ ! -f "$LAST_CHECK" ]; then
    touch "$LAST_CHECK"
    exit 0
fi

# Find new failover events since last check:
EVENTS=$(find "$LOG" -newer "$LAST_CHECK" -exec grep -l "migrate\|relocate\|failover\|fence" {} \; 2>/dev/null)

if [ -n "$EVENTS" ]; then
    DETAILS=$(grep -E "migrate|relocate|failover|fence" "$LOG" | tail -5)
    /usr/local/bin/notify-slack.sh "HA Event detected:\n$DETAILS" "warning"
fi

touch "$LAST_CHECK"
SCRIPT

chmod +x /usr/local/bin/ha-monitor.sh

# Check every 2 minutes:
# Add to crontab:
*/2 * * * * /usr/local/bin/ha-monitor.sh

While webhook notifications keep you informed about specific events, having a full dashboard view of your Proxmox environment on your phone is equally valuable. ProxmoxR complements webhook alerts by giving you real-time access to node status, VM states, and resource usage — so when you receive an alert, you can immediately check the situation from anywhere.

Summary

Proxmox VE 8's notification system combined with webhook scripts lets you receive real-time alerts on Slack, Discord, or Telegram. Set up notification scripts for each platform, hook them into vzdump for backup alerts, and monitor HA events with a cron-based log watcher. This gives you immediate visibility into critical events across your Proxmox infrastructure, even when you are away from your desk.