MFSBACKUP/MFSRESTORE Confusion

[Sleeper]

I have read varying opinions on this.

Does mfsbackup backup partitions 3,4 and 6,7 or does it just backup the active set?

If it backs up just the active set how does it determine the active set. It could examine root= returned from bootpage -P or it could examine the hidden area of the drive that bootpage -f changes.

I bring this up becasue I would like to know if mfsbackup can indeed backup and restore a full monted drive.

[captain_video]

It only backs up the active set. The inactive set is hidden which is why it only backs up the active partitions. Mfsbackup will NOT fully backup a monte'd drive. There are other posts on this issue so you may want to run a search for them or simply scroll through the recently updated threads in this forum and the newbies forum.

[Sleeper]

Originally posted by captain_video
It only backs up the active set. The inactive set is hidden which is why it only backs up the active partitions. Mfsbackup will NOT fully backup a monte'd drive. There are other posts on this issue so you may want to run a search for them or simply scroll through the recently updated threads in this forum and the newbies forum.

That is what I thought.

I have read the other threads.

My question pretains to the method that mfsbackup is using to determine the active set.

I am writing scripts and I want to backup the hidden sets with some other tool. How can I determine(see that they are hidden) them? How does mfsbackup see or not see them.

So thank you kindly for your reply, but the answer is still unclear.

[captain_video]

Use the bootpage command from bash to see which is the active partition. Look in cobelli's guide or d7o's tutorial for the monte hack to see how to use this command. You'll need a copy of johnnydeath's boot CD or download the montestuff.zip file from the twinbrothers ftp site to get the bootpage program. With your Tivo drive mounted in your PC as secondary master, the command will be:

bootpage -p /dev/hdc

You will get a response in the form of root=/dev/hda7 or root=/dev/hda4. If it says hda7 then the filesystem is in partition 7 and the kernel is in partition 6. If it says hda4 then the filesystem is in partition 4 and the kernel is in partition 3. I think you may actually get the response as hdc4 or hdc7 since that's where the Tivo drive is mounted. In either case, it's the partition identifier you're interested in and not so much the drive designation.

You can copy the inactive partitions to your Windows drive using the commands in d7o's monte guide or my modified version that I just posted in the monte thread. Make a backup using mfsbackup and then restore the imgae to another drive using mfsrestore. Copy the inactive partition images from your Windows drive back over to the Tivo drive for a complete backup and restore.

[ericchile]

I think what he is trying to do is make mfsbackup back up a monte system by doing two backups...

To restore maybe restore one... save the partitions to another harddrive.

Restore the second, then move the other paritions over...

Is that what you trying to do?

[Sleeper]

captain_video,

Thanks again for the reply.

I am well versed in the bootpage command.

Are you indeed saying that mfsbackup uses bootpage -p
to determine the active partition set?

If this is indeed the case, I could store the current bootpage -p results, rewrite the alternate root= on the bootpage and have mfsbackup backup the real root, then restore the bootpage. The backup would contain everything except the u5 kernel and fs. I am aware that if restored that the bootpage would point to an unbootable null-initrd'd kernel and the system would not boot. I can handle that.

There may be other ways that mfsbackup determines the active partition set. I say that because bootpage -f flips the boot flag on partitions 3 & 6. So it is possible that mfsbackup is looking directly at the partition table and doesn't give a hoot about what bootpage -p returns.

Regards,

[ericchile]

Nothing like testing a theory... Let us know...

[Sleeper]

What I'll probably do is examine the root partition that bootpage -p returns, subtract one and examine the kernel with md5sum and compare that to the 3.1u5.

If I determine that the system is booting a 3.1u5 kernel than I will ask if the system is monted. If so then I will store the bootpage, rewrite it and perform the backup. After backup is complete I will restore the original bootpage.

All this of course is hinged upon whether mfsbackup uses bootpage to determine the boot and root partitions. Wish I knew this for sure.