Forum Discussion
AltostratusAdd servers to pool, but don't want them used unless no other servers available
We are working on a data center migration and will be moving our Exchange production first, leaving our DR to handle mail. Currently our DR servers are on a 15 minute delay for synching with production. The DR servers are not part of the exchange pool. What we would like to do is add the 3 DR servers to the pool, but not use them unless all 4 production servers are not available. Would this setup work
Configure it using Priority Group Activation and set the Group Activation to 1. Then set the Prod servers to priority 10 and the DR servers to priority 5. Going through F5 university training it sounds like it will load balance to all servers in the highest priority. Then it will not use DR as long as there is 1 prod server available. If all of prod is down, then it will add all servers with a priority of 5.
Am I correct in that assumption, or will it only add 1 server from the highest available priority?
Thank you for any assistance.
3 Replies
SSellIn addition, if my thoughts are correct that we can use the Priority Group Activation for this, the VIP is already configured and working not using that. If we change the configuration, would it take the VIP down momentarily while reconfiguring it?
gsharriYour understanding is correct. All of the priority 5 pool members will receive traffic if there are no priority 10 members available.
There will be no impact on the VIP traffic when making this config change.
David_LarsenEmployee
You are correct. To be specific though in order to keep the DR servers from having any traffic before you configure the priority activation group you would want to add the Node first, disable the node, then add the servers to the pool and configure their priority numbers. The higher the priority the higher it recieves traffic. You can set DR to only go active if there are less than the desired number of prod servers. Do this by going into the pool settings and enabling pool priority group activation on the members tab. Set the number to 1 above the number of prod servers you need in service to add the secondary priority group. So if you set the number to 1 then as soon as 0 prod servers are available all the priority 1 servers will become active. It will add all the servers of the next highest priority group.
In answer to will it take the VIP down when reconfiguring it. It will not take the VIP down. It will only impact new connections. The old connections will continue to use the old settings.
