I had to upgrade several F5 load balancers from 11.5 to 12.1 in the last weeks. Usually updating F5 is quiet easy, but there are bugs or annoyances you should know:
- Sometimes F5 asks for re-activating after the first boot into the new version. It seems that you have to install the new version in a specific order to prevent this: BIGIP-Firmware, licence re-activate, BIGIP-Hotfix, Restart.
Remember the appliance has to be in stand by mode when re-activating the licence.
- If the F5 asks for licence re-activation after reboot, it should be easy to re-activate. But even after licence activation, F5 is not working correctly. The SNMP MIB for LTM is not complete. You have to reboot again to activate the LTM SNMP MIB tree again.
- When switching from 11.5 to 12.1 the SNMP MIB changed. Serious manufactures that special care to keep the SNMP stable and compatible. F5 doesn’t they changed data types from 11.5 to 12.1 which means you have to update the MIB database. On the other hand if you do, you cannot query those OIDs from older machines. That’s why other manufactures never change data type, The correct way is to add new OIDs wait some years and deprecate the old OID. F5 doesn’t. Here’s a diff part of mibs_f5/F5-BIGIP-LOCAL-MIB.txt:
- ltmNodeAddrStatCurSessions Gauge, - ltmNodeAddrStatCurrentConnsPerSec Gauge, - ltmNodeAddrStatDurationRateExceeded Gauge + ltmNodeAddrStatCurSessions CounterBasedGauge64, + ltmNodeAddrStatCurrentConnsPerSec CounterBasedGauge64, + ltmNodeAddrStatDurationRateExceeded CounterBasedGauge64
- Beside this breaking incompatibility between 11.5 and 12.1, they also changed some value names, which breaks software that used these names. This is not a bug but still annoying. Remember: an API has to be stable and backward compatible.
inband(2), - forcedUp(3), + forced-up(3), up(4), down(19), - forcedDown(20), - iruleDown(22), - inbandDown(23), - downManualResume(24), + forced-down(20), + irule-down(22), + inband-down(23), + down-manual-resume(24), disabled(25)
Versions: F5 LTM 11.5.1, 11.5.3 and 12.1.1