How to set up a backup/failover server properly?

[ghurty]

What is the best way of configuring a second server so that you will fail-over if the first server goes down?

How would you do it automatically without having to reconfigure the phones?

Also, if you are using a T1 line, how can you have both boxes connecting?


Thanks

 

[blanchae]

These are excellent questions and are part of Asterisk's growing pains into a mission critical product

Also, if you are using a T1 line, how can you have both boxes connecting?

There's several manufacturers that provide equipment for T1 failover: Rhino, Redfone and ISDNguard for example.

 

[jroper]

Hi

You could look at HA / DRBD as well.

If this is beyond you, then Linbit will offer some consultancy to put it together for you.

Joe

 

[ghurty]

Hi,

Thank you for the pointer for HA/DRBD. I found a lot of tutorials for HA so that wont be the problem, it looks like DRBD is harder.

I found this tutorial:
http://support.red-fone.com/downloads/elastix/Elastix_HA_Cluster.pdf

From a quick glance, with the obvious modifications, would it work for PiaF?

Thanks

 

[Linetux]

Yes, it will work. You might not want it to, however... I found that while I got it working, the difficulty came any time I needed to change or update anything... keeping two systems in sync like PIAF wasn't fun. But it's very doable with proper discipline and a proper dev/production setup.

 

[ghurty]

So what would you suggest is the best way to have the servers be relatively the same.

Thanks

 

[Linetux]

As I said on the other thread, do regular routine backups at intervals you can live with (hourly? daily?), and rsync the data between them.

The likelyhood of something happening where you actually need full redundancy is slim-to-none for most installs.

Most folks think they need redundancy - when in fact what they need is to get back up and running quickly. Only plan for and promise what they need, not what they think they want.

But this is how I would probably do it, based on the little bit of information I know about your situation. You need to figure these things out on their own - but I'll warn you, you don't want to experiment with this stuff on a client that really does need it.

 

[jroper]

Only plan for and promise what they need, not what they think they want.

is very good advice.

The manager's lament, "I know it's what I asked for, but it is not what I wanted" can be all too common.

I would recommend regular backups and a warm standby for simplicity. I have played with HA DRBD. and although making it work is easy enough, failing back, particularly in a split brain scenario requires a high degree of technical knowledge and know-how.

Joe