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Legacy Forums => Experienced User Forum => Topic started by: Paul on November 13, 2003, 03:21:28 PM

Title: Redundant/Backup Server?
Post by: Paul on November 13, 2003, 03:21:28 PM

This is more of a general Linux question rather than e-smith specific, however I would appreciate any suggestions:

I would like to have a redundant/backup server setup ready to drop into production should the primary server fail. These are the constraints/requirements:

a) Backup server is different hardware

b) Apx 5GB of files in ibay

c) MySQL Database

What is the best way to go about doing this?

Thanks!

Title: Re: Redundant/Backup Server?
Post by: Herculito on November 13, 2003, 05:45:44 PM

Hi Paul,

There is a howto document describing how to install the high availability for e-smith.Follow this link for more info !!!

http://www.e-smith.org/docs/howto/contrib/SME_High_Availability_How-To.htm

Grtz,

Herc

Title: Re: Redundant/Backup Server?
Post by: Derek on November 13, 2003, 08:00:45 PM

I've been experimenting with this using rsync and ssh-keys using these two posts as a guide:

http://forums.contribs.org/index.php?topic=15962.msg61625#msg61625
http://tehvand.com/tehvand/tehvand-main.cgi?page=projex&project=rsyncmigrate

I have a backup server with similar hardware and disk capacity as my production server. The same SME version is installed minus services like DHCP, PDC, etc...so that it doesn't conflict with the production server. I used ssh-keygen to set up dsa keys so that root on the production server can login to the backup server without a password. Then I set up a Cron job that does a command something like this:

rsync -avzP --delete --exclude-from=/root/exclude -e "ssh -c blowfish" :/ :/

(This is from memory, sorry for any syntax errors)

Where "/root/exclude" is a text file that contains this:

/lost+found
/mnt
/proc
/tmp
/var/tmp
/var/lock
/var/run
/var/spool/squid/

To bring the backup server online, do this:

/sbin/e-smith/signal-event post-upgrade
/sbin/e-smith/signal-event reboot

Then login as admin and re-configure the server for the new hardware.

The one major problem I encountered was that the backup server started a DHCP war with the production server even before the post-upgrade command was given. I basically put the project on the backburner at that point. Hopefully this gives you something to start from. If you have success, please report back.

Regards,

Derek

Title: Re: Redundant/Backup Server?
Post by: Walter Padgett on November 13, 2003, 11:15:47 PM

Good Afternoon,

I'm very interested in this issue with 5.1.2. Have you attempted to upgrade the 5.1.2 to 5.6 after creating this mirror server? I'm to the point of staying a little behind because of the stability of the contribs and other points of interest. I'm aware of all the issues / vulnerability issues but I have yet to be seriously attacked by any type of hacker or anyone else for that matter. This doesn't discount the need for prudence.

Later

Wally