[ILUG] DNS based failover for ftp servers?

[Sarunas Vancevicius]

On 5 Feb 2007, at 20:29, Conor Daly wrote:

> A recent failure hung the machine to the point where an ftp connection
> would hang waiting for a response.  The machine would respond to  
> pings.  I
> took the machine down for repairs and booted another to receive the
> incoming ftp files.  I just gave it the primary machine's ip address.
>
> In the course of considering failover possibilities, I note that  
> something
> that manages to detect the hung machine would not be able to take  
> over the
> task since the hung machine's ip address would be still in use.

Would it not just be easier to use a virtual IP for ftp.example.com  
and just have a heartbeat between ftp1 and ftp2 machines?

For example, if the heartbeat, Nagios' check_ftp plugin or even Monit  
detect that the FTP server is not responding, the virtual IP take  
over would be initiated by ftp2 box; a simple script to kill the  
heartbeat on ftp1 should be enough for this to happen.

Take a look at http://www.linux-ha.org for more info.

Sarunas