Apt-get upgrade on mailserver

[klangen]

Hi!

I'm about to patch a Postfix mail server that I setup following the Virtual Users And Domains With Postfix, Courier, MySQL And SquirrelMail Ubuntu 8.04 and I noticed there are a lot of packages that need an upgrade.

I have a question about the behavior of apt-get upgrade. Will any of the installed packages be affected before the reboot?

I was thinking I that maybe there could be complications upgrading while a lot of people are accessing their mail etc.

Is it safe to just run the upgrade or should I download the packages first and bring down the network connection before I run the upgrade?

thanks in advance!

[_X_]

I have never had any problems with apt-get update/upgrade procedures and on rare occasions i restarted/rebooted server. In most cases apt-get procedure restarts services/daemons that were updated so you don’t need to reboot.

Before any update of services, they are shutdown, patched and started again. It all goes very quickly so not too many users should experience problems.

Of course something can always go wrong :)

[klangen]

Thanks for the fast reply. I think I'm gonna play things safe anyways.

A few minutes of downtime is better than having mail coming in when the system is broken. If I bring the connection down/put it on a different network then I can make a snapshot(virtual machine) before I upgrade and then revert to it if something goes wrong without having to worry about mail getting lost.

Maybe I'm being too careful... :)

[_X_]

Well that is the safest way in case you host a server with lot of mail traffic.

But the whole update process is actually built to be done "on-the-fly" without any downtime. Actually this is the segment where Linux servers are better than most other solutions and one of the main reasons why are they used in first case.