Lease File of RAM Disk

[Simon Hobson]

Waqas Asghar <waqas.asghar at aol.com> wrote:

> The lease file on my servers are placed on a RAM DISK,now when I will be rebooting the server the RAM disk will be lost & I would have to recreate it.
> 
> What should I do for the lease file in this case should I take a backup of the lease file and place it on the new ramdisk and start the server or should I start the server with an empty lease file.

You should do neither of those - you should put your leases file on persistent storage. If you don't then sooner or later you *WILL* lose your leases file and that will cause you a truckload of problems as your DHCP servers will no longer know what has already been leased to which client.

However, when you say you have an "active/backup" setup, what do you mean as that is not something the ISC server supports out of the box. If you have a failover config, then I believe (but I'm not an expert and I don't use failover myself) you should be able to reboot one server, create a new empty leases file, and then that server will pull the leases from the partner. That only works if you never, ever, for any reason, restart both servers at the same time*.

* Where "same time" means any period shorter than the time it takes for one server to reboot and transfer the leases file from it's partner. Dunno about you, but even with reliable mains power and investment in UPS etc, we've still had "inconvenient events" at work :-(