Machine Replication using a CD-R?

dfn_doe asks: "Is there an easy way to replicate a very large Linux install across multiple machines using a CDR as the transfer medium?? I have 9 boxes that need to have about 9 gigs of Web, Database, and other information spread across two drives and 10 partitions and I REALY don't want to do it manually. Any utilities? Any suggestions? In case anyone is interested this is for serving a large distributed database to a secure Web Server." Using a CDR? That's odd, if you have a newtork, you should be using that to automate installation as opposed to burning loads of CDs (not to mention the installation). What do you all think?

Comments

Ghost will do the job

[Anonymous Coward]

With identical hardware setups on all, networked together, install everything as you want them to be on one of the machines. Use the Ghost disk to use that image on all of the rest. I haven't seen a large operation use anything else. You can set the disk up to start ( 5 mins) remove the floppy and move to the next one. It may take a while depending on the amount of data being set up, but you can get it started in under an hour, and take a nap. With a dump from CDR, you have to let the image copy from one, finish, and then move on to the next one. Boring.

You could possibily make a boot disk, with a kernel with iso9660 compiled in, setup a script to run through Fdisk, format for ext2fs, dump everything to the drive, and then run lilo with a premade lilo.conf, however you run into a problem. File attributes. I dont know if it is possible to use a different file system on CD's, (Rockwell?) that uses correct file attribs. My vote is still for Ghost.

If you cant get ahold of ghost, how about a boot floppy, which mounts an NFS partition on your master copy, and moves them over? You would still have to scrip fdisk, format, and lilo, but it could work, albeit not as easy as Ghost.

Toodles D. Clown

Try a Plextor CD-R drive

[Anonymous Coward]

Plextor CD-R drives (specifically the 8x/20x I bought a few months ago) come with a customized version of Ghost which will write a drive image to a CD. It includes support for bootable CDs, and it's a pure DOS application, which means it might work under DOSemu (does DOSemu support SCSI?). Unfortunately, the program is locked to work only with Plextor CD writers - although you can (obviously) restore with any 'ol CD-ROM drive.

I recommend the drive though - it's fast and haven't made any coasters yet.

Jeff

jdubin
at
world
dot
std
dot
com

Custom boot disk

[Anonymous Coward]

What a did to replicate 2 GB installations is to make my own custom boot disks.
It is rather easy:

• One disk with a linux kernel and lilo
• One compressed ramdisk (so you can put about 1.44 MB compressed there: enough for libc, bash, ifconfig, modules, ...). Hint: the way to test the ramdisk is to do 'chroot' after each change, on a live Linux, before writing it to a real floppy. VMware can also help to finalize boot+root disk.

The compressed ramdisk should have the tools to set up the network ; you can add whatever you want provided it is not big (telnet, ftp, jed, ...). Personnaly I use 'ttcp' to transfer bunch of data ('ttcp -r -s' on the receiving side outputs what 'ttcp -t -s server_name' receive on stdin ; useful for pipped tar).
If you need more than 1.44 MB compressed, newer kernels (2.2.9+) allow you to have bigger harddisk.

Alternatively you can mount a (big) ramdisk on / and a burned CDrom on /usr (/sbin, /bin ...), and boot cdroms instead of floppies.

How about moving the drives?

[Anonymous Coward]

Connect all of the "/" drives to one system and dd one *entire* drive to the next. Or make the partitions and do a cp -a. Then put in the "/usr." Et cetera (ad nauseam) If you want to spend money, you can do the same thing with a "disk duplicator."

Better yet

[Anonymous Coward]

Over the last week, I have duplicated 1 Netware 5 server across a small LAN using ImageBlaster made by Alteris. There is almost no setup, and it operates on a master/slave principle. This means that it is not necissary for you to create an image, but only set up the master to broadcast the current info on the drive. These servers had 18gig SCSI drives, (17.9 in a netware partion, and 50meg for dos), and it takes about 45 minutes across the 100Base-T network. Goodluck, and e-mail me @ alexrose@rocketmail.com if you have any questions

Machine replication over a network

[gavinhall]

Posted by einhirn:

Hi!
Work on NETPIPE is in process. It's a tool a friend of mine works on. It uses UDP broadcasts to
distribute data piped into the Server to all of the clients, which pipes the data out again.

bye

I released a GPL package that will ghost drives

[killbill]

I wrote a package (backburner, see www.freshmeat.net) that allows just this sort of thing. You will still need to use dd (and gzip if you wish), but it will do drive image backups (using dd) or filesystem backups (using tar) and allows gzip or bzip to be used as well.

They are a small and simple stream based set of perl scripts. Documentation includes both backup and restore scenarios for just about anything you want to do.

There are 50 to 100 people using this now, and most are having pretty good success.

Sorry I did not see you post sooner, hopefully you are still following the thread.

Replication using CD R

[Mikal]

Surely you would be better off using a product like Ghost to make a disc image and then dumping that image onto the new disks?

This could be done over the network. Ghost runs on DOS though.

Don't forget dd!

[PeterD]

Some friends of mine recently set up a Beowulf cluster, and they had to replicate what was on a number of machines. After not having much success with Ghost, they ended up using dd.

I guess this would mean you would have to physically mount each disk inside a machine one by one, but provided there is a small number of machines, this should be ok.

Having said all this, the ghost (or even cdr) may work great for you ;)

Good luck!

Interested in that sort of replication myself...

[daveman_1]

I have often thought that CD-Rs could produce an efficient and cheap backup medium for say, a "perfect system install". If you figure out how to do this, let me know...