dan1 wrote: >> Hello, >> >> I would like to replace one of the disks in a raid 1 array (software >> raid) in centos 4.4 for the purpose of >saving the removed drive as a >> backup of the system. Replace it with a new disk and have the raod >> >resync. That way the removed disk can be used to restore the system >> to that point in time if something >dramatic occured. >> >> I have a number of questions, I can’t find the answers to and I don't >> have a system I can play with to see >how the software behaves: >> >> 1) Do I need to partition the replacement drive or will the system do >> it after reboot? >> >> >> 2) Should I break the raid before replacement or just shutdown, >> replace and reboot? >> >> >> 3) I have also read that acronis 10 rescue CD can be booted and take >> a system image that way but I >have not tried that yet.. >> >> In general, are these approaches a good idea for generating an >> offsite image backup?? >> >> Any help or input would be appreciated. >> >> Thank you, >> >> -ed- > > > Hello, Ed. > We will most probably have to talk together. I have the exact same > purpose than you have. I am working like this since several years and > it is absolutely great (with mdadm software raid 1). > I do even go further: I synchronise remotely a complete system on a > local software raid system with rsync and then I can boot up the > backuped system whenever I want, and it will just be a working and > bootable backup mirror, on another system. But it is not always so > easy, problems do arise doing this, and I am working on it. > > To answer your questions: > > 1) You need to fdisk your partitions yourself on the disk, exactly the > same way the source partitions have been done, it is not done > automatically. Once this is done, you need to add the partitions to > the working md array. It takes time to synchronise everything. All > depends on the speed of your disk transfer, but if you have about > 50Mbytes/sec, you need more than a hour for a 200 Gbytes array. > Use sfdisk to partition the new disk eg. sfdisk -l /dev/hda | sfdisk /dev/hdb [snipped]