Troubleshooting Device Polling Issues

When Server Scout isn't collecting data from your monitored devices, the issue typically lies in one of several key areas. This guide will walk you through systematically diagnosing and resolving device polling problems.

Understanding Device Polling

Server Scout monitors network devices (switches, routers, storage arrays) using a designated poller server that runs the scout-agent. This agent connects to devices via SNMP (UDP port 161) or IPMI (UDP port 623) and collects metrics every 60 seconds. Unlike server monitoring, device updates occur less frequently, so allow time to see changes.

Initial Verification Steps

1. Check the Poller Server Status

First, ensure your designated poller server is online and the scout-agent is running:

sudo systemctl status scout-agent

If the service isn't running, start it:

sudo systemctl start scout-agent
sudo systemctl enable scout-agent

2. Verify Network Connectivity

Test connectivity from the poller server to your device:

For SNMP devices:

telnet [device-ip] 161
nc -u [device-ip] 161

For IPMI devices:

telnet [device-ip] 623
nc -u [device-ip] 623

If these connections fail, check for network issues or firewall rules blocking traffic.

SNMP Troubleshooting

3. Verify SNMP Tools Installation

Ensure the necessary SNMP tools are installed on your poller server:

# Debian/Ubuntu
sudo apt install snmp-utils

# RHEL/CentOS
sudo yum install net-snmp-utils

4. Test SNMP Credentials

For SNMP v2c, test the community string:

snmpget -v2c -c [community-string] [device-ip] 1.3.6.1.2.1.1.1.0

For SNMP v3, verify authentication credentials:

snmpget -v3 -u [username] -a [auth-protocol] -A [auth-password] -x [priv-protocol] -X [priv-password] [device-ip] 1.3.6.1.2.1.1.1.0

If you receive authentication errors, double-check your credentials in both Server Scout's configuration and the device's SNMP settings.

5. Common SNMP Issues

• Wrong SNMP version: Ensure the version selected in Server Scout matches what the device supports
• Incorrect community string: Verify the community string is exactly as configured on the device (case-sensitive)
• SNMP disabled: Check that SNMP is enabled on the target device
• Access restrictions: Some devices restrict SNMP access by IP address or interface

IPMI Troubleshooting

6. Verify IPMI Tools

Check that ipmitool is installed on the poller server:

# Debian/Ubuntu
sudo apt install ipmitool

# RHEL/CentOS
sudo yum install ipmitool

7. Test IPMI Credentials

Verify IPMI connectivity and credentials:

ipmitool -H [device-ip] -U [username] -P [password] chassis status

Examining Agent Logs

8. Check Scout Agent Logs

The scout-agent logs provide valuable debugging information:

journalctl -u scout-agent -f

Look for specific error messages such as:

• "Connection timeout" (network connectivity issues)
• "Authentication failed" (credential problems)
• "No response from device" (device configuration issues)
• "Permission denied" (access restriction problems)

For historical logs:

journalctl -u scout-agent --since "1 hour ago"

Firewall Considerations

9. Check Firewall Rules

Ensure your poller server can reach devices on the required ports. On the poller server:

# Check outbound rules
sudo iptables -L OUTPUT
# Allow SNMP traffic if blocked
sudo iptables -A OUTPUT -p udp --dport 161 -j ACCEPT
# Allow IPMI traffic if blocked
sudo iptables -A OUTPUT -p udp --dport 623 -j ACCEPT

Also verify that the target devices aren't blocking incoming SNMP/IPMI requests.

Next Steps

If you've worked through these steps and are still experiencing issues, check the device documentation for specific SNMP/IPMI configuration requirements. Some enterprise devices have additional security settings that may need adjustment.

Remember that device polling occurs every 60 seconds, so allow adequate time to observe whether your changes have resolved the issue.