Last Modified: Oct 17, 2023
Affected Product(s):
BIG-IP LTM
Known Affected Versions:
11.6.2 HF1, 11.4.0, 11.4.1
Fixed In:
11.6.0, 11.5.1 HF6
Opened: Jul 10, 2014 Severity: 2-Critical Related Article:
K15628
When TMM is restarted on the standby slot or on an HA peer, one or more HA connections may not be reestablished. This occurs based on which TMM is designated to make the outbound connection to the active peer; when mirroring across appliances, the connection may originate at either the active or standby peer.
If failover occurs in this state, some portion of the flows will not have been mirrored and will be reset.
To determine if this is the case, use tmctl -f /var/tmstat/blade/tmm<n> ha_stat, for each of the tmm<n> files in /var/tmstat/blade/. If any of the selected connections is listed as 'none', then that TMM is not connected to the peer.
Need to modify profile tcp _tcp4_ha_defaults in /usr/lib/tmm/tmm_base.tcl and add "syn_maxrtx 3" 1. mount /usr -o remount,rw 2. make copy of /usr/lib/tmm/tmm_base.tcl 3. In /usr/lib/tmm/tmm_base.tcl find profile tcp _tcp4_ha_defaults and add "syn_maxrtx 3" profile tcp _tcp4_ha_defaults { idle_timeout 30 keep_alive_interval 1 syn_maxrtx 3 maxrtx 4 rcvwnd 4194304 ... 4. Restart TMM. (traffic would be impacted if this is a active device) 5. mount /usr -o remount,ro This has to be done on both units. If there is more than one blade tmm_base.tcl has to be modified on all blades before restarting TMM.
Now, when TMM is restarted, all HA connections are reestablished.