Forum Discussion
Jason_Mahony_10
Nimbostratus
NimbostratusNode failure redirect
Hi, I really not familiar with iRules but I could use a hand.
I'm running Big IP version 9.0.3. Essentially, I have a pool running HTTP and HTTPS on 2 servers. One of these servers should be running SIP as well. If the server running SIP goes down, I want the other server to start running SIP. So, what I need is an iRule that checks if a node/member is still running a particular service and if the node stops running this service, redirect the traffic from one pool to another.
Any help would be really appreciated.
10 Replies
- Also, here's a basic rule for directing traffic to different pools based on the status of a pools members via the monitors:
rule pool_check { if { [active_members poolA] > 0 } { pool poolA } else { pool poolB } }
The command active_members returns the number of members in the pool that are reported as UP. Note: If you don't have any monitors and the members are reported via the GUI or bigpipe as UNCHECKED, then active_members will return 0. 
Brandon_High_10pool SIP_servers { min active members 1 min up members enable member 1.2.3.4:80 priority 1 member 6.7.8.9:80 priority 2 monitor all tcp }
According to the docs, priority group 2 would be active first, then group 1. Or is this another instance where the docs are wrong?- This is likely another case where the docs are wrong. Mullet and I checked the code and lower number's are used before higher numbers (eg, 1 is a higher priority than 2).
Rick_Mitterer_1Hi,
I'm not seeing that on our system. We have a web server pool at p 3 and then a down server at p 1 ... the down server should only get traffic if all the p 3 servers are down. Which seems to be the case. If what you say is true...what indication should we be seeing?
Regards,
Rick Mitterer
NeimanMarcus.com
lucien_Caumart2Hello All,
You post the following rule :
rule pool_check
{if { [active_members poolA] > 0 }
{pool poolA}
else {pool poolB}}
But it is possible to put a specific comamnd to automatically disable the PoolA when thi one goes down ?
Best regards,- I don't fully understand your question, can you give some more detail?
- lucien_Caumart2Hello,
Sorry for my bad english :o) .
My wishes:
I have a vip and behind this vip I have 2 nodes
NodeA (Master Node), priority 254
NodeB (Backup Node), priority 128
If nodeA goes down, I would like to disable this one with an Irule.
Does it possible ?
Best regards,
Thanks
Lucien - The good news is that yes, you'll be able to do that. The bad news is that you'll have to wait until the next release ships to get it.
I believe I've previously posted a rule that uses an array to track the nodes and avoid using them if they've had several failures.
Click here: http://devcentral.f5.com/default.aspx?tabid=28&view=topic&forumid=5&postid=3426 - lucien_Caumart2Hello UnRuleY,
Thank you for your quick response.
Do you have some documentations for the directive LB::reselect ?
Do you have a date for this new release (9.2)
Best regards,
Lucien - Chuck_Adkins_13Running 9.04
With this setup I am getting priority 2 nodes when priority 1 nodes are up:
pool www.domain.com {
lb method member least conn
min up members enable
min active members 1
monitor all health-check
member 10.1.1.2:80 priority 1
member 10.1.1.3:80 priority 1
member 10.1.1.4:80 priority 1
member 10.1.1.5:80 priority 1
member 10.1.1.6:80 priority 2
}
Please advise
