Bug ID 1006449: The default size of the subagent object cache may lead to slow SNMP response time and high mcpd CPU use

Last Modified: May 02, 2024

Affected Product(s):
BIG-IP Install/Upgrade, TMOS(all modules)

Known Affected Versions:
15.1.0, 15.1.0.1, 15.1.0.2, 15.1.0.3, 15.1.0.4, 15.1.0.5, 15.1.1, 15.1.2, 15.1.2.1, 15.1.3, 15.1.3.1, 15.1.4, 15.1.4.1, 15.1.5, 15.1.5.1, 15.1.6, 15.1.6.1, 15.1.7, 15.1.8, 15.1.8.1, 15.1.8.2, 15.1.9, 15.1.9.1, 15.1.10, 15.1.10.2, 15.1.10.3, 15.1.10.4, 16.1.2, 16.1.2.1, 16.1.2.2, 16.1.3, 16.1.3.1, 16.1.3.2, 16.1.3.3, 16.1.3.4, 16.1.3.5, 16.1.4, 16.1.4.1, 16.1.4.2, 16.1.4.3, 17.0.0, 17.0.0.1, 17.0.0.2, 17.1.0, 17.1.0.1, 17.1.0.2, 17.1.0.3, 17.1.1, 17.1.1.1, 17.1.1.2, 17.1.1.3

Opened: Mar 25, 2021

Severity: 2-Critical

Symptoms

After upgrading from a 13.1.x release to a later release (such as 15.1.x), BIG-IP CPU utilization increases and SNMP is slow to respond.

Impact

SNMP queries take an unusually long time to return data, and BIG-IP CPU utilization is higher.

Conditions

SNMP client repeatedly polls BIG-IP for OIDs in multiple tables over a short period of time.

Workaround

To the file /config/snmp/bigipTrafficMgmt.conf, add one line with the following content: cacheObj 16 This could be accomplished by executing the following command line from bash: # echo "cacheObj 16" >> /config/snmp/bigipTrafficMgmt.conf After the above config file has been modified and saved, the "snmpd" daemon must be restarted, using one of two command variants: (on a BIG-IP appliance or VE system) # bigstart restart snmpd (on a a multi-slot VIPRION or vCMP guest) # clsh bigstart restart snmpd (However, this adjustment will be lost when the BIG-IP software is next upgraded.)

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips