been put in a fix and was wondering if any one could help.
Getting my first server soon and going to co-lo it ... but need some advice on the appropriate backups to run ...
Server - RH7.2 with Ensim
Will purchase 3 HDD and was thinking of running them as follows :-
HDD (A) 80GB Main Drive - install RH 7.2 with Ensim and all the patches and use this as the main drive
HDD (B) 80GB Secondary Drive - install onto the server as a secondary drive and carry out a nightly mirror of the Main drive, what commands or scripts can I use here ? Rsync ? MirrorDir ? Or would you suggest an online Raid 1 mirror ? How can I achieve that when there isn't a hardware Raid card installed .... ?
HDD (C) 80GB Additional Drive - will be kept offsite in my office on another spare PC connected to the internet via a 512K DSL line. I will need to get an exact replica of HDD(A) on a nightly basis via a cron job. any suggestions here ? Rsync ? Mirrordir ?
Oh.. when I mean exact replica .. I mean everything from OS to config files to user data to mysql etc ...
Bandwidth in and out of the server isn't a problem - have lots of it.
Would appreciate any help rendered. Thank you.
PS - would you consider this kind of backup / RAID relatively okay for a simple web and email server ?
If my thinking is correct you would need 347 hours to copy the whole 80 gig's through the line. This would be 14 days to copy them. Now think about how much time you have every night to make the backup ? 2 hours ? 4 hours where the server is not on often visited ?
Ok you will only need the full backup one time and then increment it, but thats not a backup because you never can go back to a previous version (if a file is damaged or someone has compromised your system, the rsync will copy them to your local box and the box is compromised, too).
The best way is IMHO to get a streamer with a minimum of 7 tapes and make a daily streamer backup.
this primary depends on how many data there is to backup. If theese are the whole 80gig's then there is no really low price solution.
Here are some ways it is possible (first only backup, after that the redundancy) :
1. Ask your co-lo provider if they offer a backup service. Perhaps they have a big library and you only need to install an agent and pay some small fees per month ?!
2. Buy a tape drive, a scsi controller and some tapes. Remember that on a 40/80 Gig's Streamer not really 80 Gig's are fitting because the 80Gig's are compressed and its not sure that you have a compression ratio of 2:1. (oh my bad english *smile*)
First of all calculate how much there is really to backup after that take a look for a good streamer which can handle the calculated sum in the time you have every night.
1. IDE RAID. You can buy a small IDE 133 RAID Controller and two (or more, max. 4) 80 Gig IDE 133 Harddrives. The controller is round about 50$ and the two hard drives 120$ (don't know the exact prices). This is a nice and low cost solution for a small Raid. With this system you can build up a raid 0,1 or 10.
2. SCSI RAID (my preffered one). Buy a scsi raid controller and 2 or more SCSI Harddrives. This costs much more, but you can often use the raid controller as a normal scsi controller, too. So you can connect it with the streamer. With this system you can build up a RAID 0,1,5 or 10.
This all depends on what you need. If you need a very fast system i would prefer a scsi U160 Raid Controller with the appropriate 10k hard disks. If you can live with a slower system, yes IDE is slower than SCSI, you can use the IDE System.
thanks for the fanastic information ... appreciate it a great deal.
any links to a HOW-TO setup a software RAID on a RH 7.2 with Ensim ?
I'm trying to evaluate the possibility of running a software RAID.. I understand the fact that my CPU will have to work alot harder and that having a RAID card would be more efficient... but just for this evaluation, is there any links I could get to setup a software raid ?
PS - Looking at a 3Ware 7000-2 Raid Card ... 2 port Raid Card ... support Raid 0/1 ... so I guess this would be just right for my setup .... Correct ? Any comments ?
sorry no how-to for a software raid. I've never used it because on high load systems every percent of power is needed and so its better to put in a nice raid controller with some cache (64 MB or so) and use this, thats much faster.
I think software raid is something for the first steps and it makes only sense to me if you have 1 Boot drive and 1 RAID System. And then you have again a single point of failure (the boot drive).
I personally have a IDE Raid Controller at home but not second hard drive to make a test drive, so i couldn't give you any info for this.
I've taken a small look on the 7000-2 and the only bad thing i can see is that it's not upgreadable. If you'd like to use a bigger raid system with more hard drives you need to buy a new controller. Perhaps the 7000-4 is better, but this depends on your future plans.