Re: Cheetah2 connection manager and failover arbitrator

----- Original Message ----- From: "Andrew Ford" <aford@networkip.net> To: <informix-list@iiug.org> Sent: Friday, June 06, 2008 12:53 PM Subject: Cheetah2 connection manager and failover arbitrator > IDS 11.50.UC1 > Red Hat Linux 5 > Simple HDR environment 1 Primary - 1 Secondary > Some additional CM questions not related to RAC... When the CM is started in a simple HDR environment (or complex MACH11 env I guess), should INFORMIXSERVER for the environment starting the CM always be set to the current HDR Primary? If so, scripting the automatic start of a CM in an environment where the HDR Primary can change often will need to identify which server is primary and properly set INFORMIXSERVER before starting a CM, right? If you have a dedicated network for HDR traffic, can you prevent the CM from using the DBSERVERALIAS for this network for connection redirection? Setting the s=6 option for both HDR sqlhosts entries prevents connection attempts on the HDR network for the primary SLA, which is good. But setting the s=6 option for both HDR sqlhosts entries prevents ALL redirection to an HDR (secondary only) SLA with a Warning: no server returned for SLA cheetah_sec2 [cmsm_sla.c:1117] SLA cheetah_sec2 cannot find database server for SQLI client [cmsm_main.c:1151] in the oncmsm log And finally When running two CMs to provide redundancy, could there be any issues with both failover arbitrators realizing the primary node is down and attempting a failover to the secondary at the same time. My tests don't show a problem so far, wondering if anyone can comment on if this condition is handled in the CM. I suppose a way to avoid the problem is to set the failover timeout value to N seconds on CM1 and N+2 seconds on CM2. Thanks, Andrew