Boot from recovery CD or media to edit fstab

[TechC]

Matti,
Ouch, that last line about a support agreement was painful. I am gonna have to beg one of my co workers but I appreciate the response. I had accessed that advanced recovery doc in the past when i did have a valid contract, actually I still may.I will have to check it out.

Good news is the box is up now,the root disk was still ok. Pounded out the non lvm entries from single user mode. But we lost a disk and the previous admin did not back the file system up that lived on it.

I will close this thread soon.

Thank you for your help.

James

[TechC]

Hello, issue possibly related.

The lvmtab is not there anymore. How can i recreate this lvmtab file?

Is this a serious issue?

Thank you
James

[TechC]

I see vgscan is used to recreate the lvmtab file. What are the repercussions of running vgscan .man vgscan says only to use it in catastrophic events or if it was deleted.

Not sure why it is missing.


Thanks again
James

[James R. Ferguson · Accepted solution]

Hi James:

> How can i recreate this lvmtab file?

# vgscan -a -v
# vgchange -a y
# lvlnboot -R

Now, if you have any alternate LVM links they may not be in the primary/secondary relationships that they were originally. You can see the order by either doing:

# strings /etc/lvmtab

(or)

# vgdisplay -v

To reorder alternate links to your needs, simply 'vgreduce' a primary link. This promotes the seondary link to primary status. Then 'vgextend' the link you last reduced. THis adds it back to the volume group but as a secondary link. Repeat this for all of your links as necessary.

If you have a large number of pvlinks you can simply 'vgexport' the volume group capturing the device files in a file; edit and reorder the device links; and 'vgimport' the volume group. Thus:

# vgchange -a n /dev/vgNN
# vgexport -m /var/tmp/vgNN.map -f /var/tmp/vgNN.paths /dev/vgNN
# [ ...edit /var/tmp/vgNN.paths ]
# vgimport -m /var/tmp/vgNN.map -f /var/tmp/vgNN.paths /dev/vgNN
# vgchange -a y /dev/vgNN

Regards!

...JRF...

[TTr]

Before 11.x and recovery CDs the HP servers in addition to the installation media they came with the "support media" CD or tape. There was a printed book that came with the media and it described what you could do with it. You booted from the support media just like you would with an install media and get an ISL prompt. From there you could run online and offline diags, STM and boot the support kernel to do system recovery. You would need to find both the media and the book, maybe somebody is selling on ebay.

[TechC]

Thank you Mr. James.

No wonder you are a 2 star Olympian.
I have no pvlinks so I think the set of 3 commands may do the trick.

# vgscan -a -v
# vgchange -a y
# lvlnboot -R

I can do this while in multi user mode then?
I am confused as to why the machine boots up and mounts the lvols if the lvmtab file is off.
I will have to read up on this but is this file unimportant for reasons other than displaying volume group statistics.

Thank you
James
--------------

TTr,
It's a cold world sometimes.

Thank you
James

[TechC]

Thank you all, I am closing this thread. Although I did not get the answer I was looking for I did get some good feed back on the lvm stuff and this was helpful.

James