I have some sites that must go on a redundant server system, do you know the name of the box (make and model number if possible) that needs to be stuck between the (physical) servers?.

This box would enable all sites to keep working if one physical server fails for any reason. Each physical server (a PC) would have web,ftp,database,etc. servers. The load on the servers would be balanced too.

I guess this is done by each physical server's hard disk keeping identical data as the other physical server, continuously updating the data.

Any information appreciated.

Aloha
I think you are talking about load balancing
ther ewas some discussion on this in another thread

there is a dif between round robin in that thread and load balancing

check it out
http://www.webhostingtalk.com/showthread.php?s=&threadid=10957&highlight=round+robin

also if you go here :
http://www.dell.com/us/en/esg/topics/segtopic_servers_pwrap_loadmain.htm

and read some info
these are expensive ones you cna do it with a normal box and some software or
some software has good mngmnt of it
such as windows2000
worked on a box that was 5 nodes 2 dataservers and 3 appservers used Allaire CF balancing program (name escapes me now )
so there are many ways to do this
hope this helps
I am sure others will jump in

check out linux virtual server.


http://www.linuxvirtualserver.org

i can vouch for this -- we're currently deploying it for a very large car manufacturer and it's working great.

we also sponsor the project. excellent code, excellent people, excellent product. and it's opensource/free!

raj dutt

You might want to look into CDN (cached Data Networking)

We use it for some clients, and as long as they update the cache, uptime remains 100% and sites are in the latest form.

We like it...

Joe

Well, if you can cough up the dough... :D

Do look into Cisco's range of Local Director systems. It works like the Linux Virtual Server (LVS) and is in between your server farm and the client. Such systems (including LVS) provide better service than round-robin softwares (as they just redirect, to even servers that are down) as they can check on servers that are down and avoid using it and also distribute the load based on the server specs.

Also, to make your LD redudant, you can always buy a second unit and put it as slave ;)
That is, if you really can cough up the dough :rolleyes:

Check it out, www.cisco.com