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asyadiqin
Hi,

I have 2 servers, each at different locations and running FC2. I am quite new in using Linux and would like to know if there is any solutions that I could use to, sort of redirect all http and mail the main server in 1 location to the 2nd location, should the main server goes down.

I was told about clustering, but was told that it would need both server to be on the same location. But I need something that I can use with servers on different locations.

Any help and pointers would be greatly appreciated.

Thanks,

Allie Syadiqin
hughesjr
OK ...

For the e-mail server, it is easy. You create a second MX record for your e-mail domain(s) that points to the second (backup) server with a higher priority number.

If you look at the mx records for abc.com (I just picked that out of the blue) .. with the command:

dig -t mx abc.com

you will see what I mean in the answer section:
CODE
;; ANSWER SECTION:
abc.com.                3519    IN      MX      10 mail1a.disney.com.
abc.com.                3519    IN      MX      10 mail2a.disney.com.
abc.com.                3519    IN      MX      10 mail11a.disney.com.
abc.com.                3519    IN      MX      10 mail12a.disney.com.
abc.com.                3519    IN      MX      15 mail11.disney.com.
abc.com.                3519    IN      MX      20 mail.disney.com.


They have 4 servers that are each considered the main server (a request can go to any of the four servers) ... if none of those 4 are up (with the 10 priority) the the 15 priority is tried ... if it is not up, then the 20 priority is tried).

So, create an MX record that points to your second server (with a higher priority number) and if the first one goes down, you get mail at the second one.

-----------------

For a webserver, it is different. You would have to have a way to run a DNS server that supported dymanic DNS.

You would then need to write a script that tested the primary server's IP Address (on port 80) at a certain interval, and made an adjustment to the A DNS record if the primary site was down, pointing the A Record on the DNS server to the secondary IP if the primary IP address is down. You would also have to set the DNS records (on the DNS server) to only cache for a short period of time.

These guys have a site that supposedly does this ... I don't know how well it works:
http://www.website-backup.com/index.htm
asyadiqin
Thanks for the info.

Anyway, I checked out the site you mentioned and seems that it was a commercial service. I was looking into a solution that I can installed on the server itself.

Any other solutions or recommendations?

Thanks.
hughesjr
The recommendations to do it yourself would be based on you having the following:

1. Your DNS server on site.
2. Your being able to write automated scripts to check the website.
3. Your being able to write automated scripts to update your zones on that DNS server.

If you manage your Primary DNS server as a UNIX/Linux server on site ... or if you are already using a dynamic service like ZoneEdit.com for your DNS provider ... scripts can be developed (I could do it fairly easily in a couple hours).

If you have a traditional (non-dynamic) DNS provider, you will have to pay them to monitor and switch the DNS info (like the commercial link I gave you).

Do you have your Primary DNS server located on site?
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