[ClusterLabs] Antw: [EXT] Data location

[Ulrich Windl]

>>> Seb <seb at h-k.fr> schrieb am 08.09.2020 um 16:28 in Nachricht
<nycvar.QRO.7.76.2009081606430.18136 at af3358511.vc-37-187-30.rh>:

> Hi,
> 
> 
> I'm new to clustering. My purpose is to replace our current server (web, 
> mail received and sent, mailing lists, FTP) with an active/passive cluster 
> in order to minimize the downtime.
> 
> I've read the "Clusters from Scratch" guide, which seems like a good 
> starting point (thanks to the authors). The guide does not talk much of 
> the data that is used by the services, though.
> 
> For instance, what should be done with the emails received on the primary 
> node? For the email service to keep working when the primary node fails, 
> the emails should be replicated in real time on the secondary node. On my 

You have multiple choices:

1) Use a shared disk that is used exclusively by one node at at time. On
failure, the other node uses the disk (implying fsck most likely before)

2) Replicate your data between local disks. Could be DRBD or rsync.

3) Use a HA fileserver like NFS to store your data

> Debian box they are stored in /var/mail. From the guide, my understanding 
> is that /var/mail should then be located on the partition that is shared 
> between nodes through DRBD. Is this the way to go? Should all of /var be 
> on the shared partition, perhaps through a symlink?
> 
> What about colder data, such as Apache's conf files for enabled websites?
> Should they be on the shared partition, or synchronised by hand? Should 
> all of /etc be on the shared partition?
> 
> 
> Many thanks for your guidance!
> 
> Sébastien.