Persistence Conundrum

Hi Bloitus,

 

It would help if you can post your VIP and Pool configuration. That being said are you using SNAT somewhere in this configuration?

 

 

Thanks,

 

Bhattman

Hi Bhattman,

 

 

Hope this is what you are after...

 

 

Web Virtual Server configuration and properties:

 

Name: Dev-WebTest3-VS

 

Destination Type: host

 

IP Address: 192.168.12.132

 

Service Port: 80

 

Type: standard

 

Protocol: TCP

 

HTTP profile: http (this is a default profile)

 

Address Translation: Enabled

 

Port Translations: Enabled

 

SNAT Pool: AutoMap (to answer your Snat question)

 

 

Default Persistence profile: Cookie_Test

 

 

NB:Cookie_Test Profile is a persistence profile with cookie method of http cookie insert and a expiration of 30 mins.

 

 

Web Pool Config and properties:

 

Name: Dev-WebTest3-Pool

 

Allow SNAT: Yes

 

Allow NAT: Yes

 

Load Balancing Method: Round Robin

 

Web Pool Members:

 

Member 1...

 

IP address: 192.168.12.122

 

Service port: 80

 

 

Member2...

 

IP address: 192.168.12.123

 

Service Port: 80

 

 

Workflow Virtual Server configuration and properties:

 

Name: Dev-WorkflowTest1-VS

 

Destination Type: Host

 

IP Address: 192.168.12.140

 

Service Port: 1099

 

Type: Standard

 

Protocol: TCP

 

Address Translation: Enabled

 

Port Translation: Enabled

 

SNAT Pool: AutoMap

 

 

Default persistence profile: Source_3600 (**********this has me thinking, perhaps in our tests we weren't waiting enough time for the time out to expire)

 

 

NB: Source_3600 is a source affinity persistence profile with a time of of 3600 seconds.

 

 

Workflow Pool Config and Properties

 

Name: Dev-WorkflowTest1-Pool1

 

Allow SNAT: Yes

 

Allow NAT: Yes

 

Load Balancing Method: Round Robin

 

Workflow Pool Members:

 

Member 1...

 

IP address: 192.168.12.139

 

Service Port: 1099

 

 

Member 2...

 

IP address: 192.168.12.235

 

Service port: 1099

 

 

------------------------------------------------------

 

 

I think that is everything! I'm going to retest with a smaller timeout on the workflow persistence profile.

 

 

 

 

 

Well that was it... basically member 2 in the workflow pool was offline in a proceeding test meaning that source persistance was pushing all data to member 1 and continued to do so even when member 2 came back online. After waiting over an hour test worked as originally planned.

 

 

quick question though... is there a way of reseting the persistance on a pool purely for testing purposes instead of having to wait for the timeout?

 

 

Sure, you can use:

 

 

b persist VS_NAME delete

 

 

See 'b persist help' for details.

 

 

Aaron

perfect... thanks for the assistance.

Hi Bloitus,

 

Since you have AutoSNAT with source affinity persistence on the workflow vip and pool you are basically going to see one connection gravitate towards a particular node.

 

 

I believe the easiest method to load balance them is to simply not have them directly balanced by the F5 such that one web server makes the requests directly to workflow node 1 and the other to workflow node 2. They would be indirectly balanced if that is all the workflow servers see. However, I am not sure if this is what you are looking for.

 

 

Let us know if you ever thought of going direct?

 

 

Bhattman

 

 

Hi Bhattman,

 

 

Yes i we have tested going direct from onlines to workflows which worked as expected... in our tests we were attempting to see if there was an impact on the application by routing the traffic via the LTM is this way. Effectively we would achieve the same thing by going direct however there are benefits for using a workflow pool which could be more beneficial in the long run (such as we would be able to add/remove members to the pool for maintainance without having to stop the application or scale up the number of workflow members should there be a issue with load in production).

 

 

Thanks for the assistance all!