More than 1 back-up CSS in active-active mode

[savyer]

Guys,

According to documentation only two CSS boxes can be configured for the same VIP in VIP redundancy mode (one active and one backup). However I can't find anything that can prevent addition of another pair CSS's in a backup mode for the same VIP. (one active and 3 backup)

Is there anything in code that can prevent this configuration?

I dont have more than two boxes in the lab to verify it. My goal is to have additional layer of protection - N+N

Thanks

[Gilles Dufour]

this is indeed not supported.

I believe some people outside have tried it and it was *working*.

However, can't guarantee that all functionalities will work and you will be asked to come back to a normal setup if you open a case with the TAC [whatever the problem].

Also, I don't think N+N protection is really giving you more then just 1 backup.

I would really encourage you to stay with the 1 backup only.

Regards,

Gilles.

[savyer]

Do you know what functionality might not work?

We are looking at using fate sharing and basic LBs with SSL ID & SRCIP stickiness.

Do you know if it is ever be supported in future releases?

Our customers requested us to provide more than one backup since apparently Foundry and Redline have been wooing them with this feature.

It gives at 3 backup boxes in case of rolling failures while providing load sharing.

Thanks

[Gilles Dufour]

Obviously our competitors will stress the importance of this N+N redundancy since they know we do not have such feature.

However, it is clear that his feature is really not required and do not bring any benefit.

2 devices in redundancy is more than enough.

I don't think we will support this feature in the future because, again, we don't see the benefit.

If your customer is so much interested in this, ask him to explain a scenario where 2 devices in redundancy would not be enough [don't simply say the first 2 died at the same time - if 2 die at the same moment, why not 3 ??].

The customer can buy 3 CSS, have them configured but only 2 physically connected, when 1 CSS dies, the other one will take over and a manual intervention can start the 3rd one.

Regards,

Gilles.