BOOT DISK MIRRORING in LINUX

[seenivasan]

Dear,

if possible to mirror the boot disk at rhel?same way for troublshooting LVM like HP-UX?

Regards,

[kemo]

check the attachement

[Chhaya_Z]

Hi,

Are you trying to take a backup of your boot disk such that if the original disk goes bad you can boot from the other one?

If so then you can use the dd command:

dd if= of= bs= count=

[Tim Nelson]

most newer servers have an internal raid card for the internal disk ( even on IPF). it negates the need to use OS mirroring as it is done at the HW level.

[dirk dierickx · Accepted solution]

you can set this up during the installation of RH, if you have already a live system and want to convert the disks to have RAID (software) protection, it is very difficult to setup at that stage and depending on how your disks are used right now maybe even impossible.

linux software raid wiki with all the infor you could possibly need:
https://raid.wiki.kernel.org/index.php/Linux_Raid

[Alzhy]

"Troubleshooting LVM like in HP-UX"?

By that I trust your Linux OS sits on top of an LVM scheme. And you have a neeed to have a fallback OS in case the main LVM OS VG conks out as a precautiion to patching or "accidents" - right? And so you can have an easy fallback - no?

If so - you have a myriad of choices to wit:

1) MondoRescue - easy to set up and could be acceptably "fast"
2) Alternate vgbroot where you set up a fully bootable and independent but easily refreshed (via dd or LVM snapshot) of your primay
3) SAN Boot where you use your SAN Array's snapshot capability to backup and fallback your OS.

I do wish Linux will soon have something similar to DRD (Dynamic Rootdisk -- ala HP-UX 11.31 - drd clone) or Solaris LiveUpate (lucreate, etc.). But I believe it will eventually come.