请求协助：通过SNMP获取F5设备中各节点的CPU与内存利用率

Got it, let's walk through exactly how to pull CPU and memory utilization stats for your F5 ADC's backend nodes via SNMP. I’ve tackled this scenario dozens of times, so here’s a step-by-step breakdown that should work smoothly:

Before diving into data retrieval, make sure your F5 is set up correctly for SNMP access:

• Verify SNMP is enabled on the F5 (v2c or v3 works; v3 is more secure for production). You’ll need a valid community string (for v2c) or auth/priv credentials (for v3) that allows read access from your monitoring host.
• Test basic connectivity first to rule out network/permission issues. Run this command from your monitoring server:

  snmpwalk -v2c -c <your-community-string> <f5-device-ip> .1.3.6.1.2.1.1
  

  If you get system info back (like device name, OS version), you’re good to go.

F5 stores node CPU stats in its proprietary LTM MIB. Use these OIDs and commands:

• Core OID for node CPU usage: 1.3.6.1.4.1.3375.2.1.1.2.1.7 (maps to ltmNodeCpuUsage, a percentage value)
• To pull CPU data for all nodes at once:

  snmpwalk -v2c -c <your-community-string> <f5-device-ip> 1.3.6.1.4.1.3375.2.1.1.2.1.7
  

  Example output (the trailing IP is your backend node’s address):

  SNMPv2-SMI::enterprises.3375.2.1.1.2.1.7.1.192.168.1.10 = Gauge32: 45
  This means the node at 192.168.1.10 is using 45% of its CPU.

Memory stats follow a similar pattern with a dedicated OID:

• Core OID for node memory usage: 1.3.6.1.4.1.3375.2.1.1.2.1.8 (maps to ltmNodeMemUsage, percentage)
• Pull memory data for all nodes:

  snmpwalk -v2c -c <your-community-string> <f5-device-ip> 1.3.6.1.4.1.3375.2.1.1.2.1.8
  

  Example output:

  SNMPv2-SMI::enterprises.3375.2.1.1.2.1.8.1.192.168.1.10 = Gauge32: 62
  Here, the node is using 62% of its available memory.

If you only need stats for one node, use snmpget and target its index (usually the node’s IP in decimal form):

# Get CPU for a single node
snmpget -v2c -c <your-community-string> <f5-device-ip> 1.3.6.1.4.1.3375.2.1.1.2.1.7.1.192.168.1.10

# Get memory for the same node
snmpget -v2c -c <your-community-string> <f5-device-ip> 1.3.6.1.4.1.3375.2.1.1.2.1.8.1.192.168.1.10

If you’re using SNMPv3 (recommended for security), adjust your commands to include auth/priv details:

snmpwalk -v3 -u <snmpv3-username> -l authPriv -a SHA -A <auth-password> -x AES -X <priv-password> <f5-device-ip> 1.3.6.1.4.1.3375.2.1.1.2.1.7

内容的提问来源于stack exchange，提问作者M. Gopal