Using a "remote" system to maintain up/down status of a VIP and/or pool members?

Is it possible to maintain the up/down status of a VIP (and/or its related pool/pool members) by querying a real server that is totally unrelated to the pool?

 

 

Specifically, let's say I have a VIP called "test-vip" which references a pool called "test-pool." The "test-pool" has, for example, two members: "test-pool-member1" and "test-pool-member2."

 

 

Normally, one would use some sort of health-check against the members of "test-pool" to determine if they are available.

 

 

Recently, however, I have been asked to configure the load balancer so that, instead of checking the pool members directly to determine if they are up/down, it should check for the existence of a file on a totally separate system (for example, a file named "system-is-in-maintenance-mode" on a server named "some-other-server"). If that file is present, the VIP should be unavailable.

 

 

This, as you might surmise, is intended to alert clients when the system is intentionally down for maintenance; so a fallback host will be configured to redirect clients to a "maintenance" page.

 

 

Would such an approach work?

 

 

Of course, other suggestions on how to do a "maintenance page" are welcome.

 

 

Thank you!

 

 

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Rob