[plug] Request for advice about RAID & networking problem

Thu Jan 24 06:28:54 UTC 2013

:) 
have a look at the output of the "mount" command and determine the top level file systems and what format they are :) Then a quick google for that file format and the keyword "resize" will likely suffice. 

I think you are only likely to have an issue if you have (for some reason) partitioned the harddrive and allocated specific partitions as PVs, rather then just the raw block. 

If you have, for some reason, allocated a partition as a PV, then you have a lot of fun times in front of you and I hope you have backups. Read up on resizing partitions. Can be easy, can be hard, *IT DEPENDS* :) You will learn a lot of things you will likely wish you never had to know. 

have a look at "fdisk -l" and/or "pvdisplay" and see if that's the case - if the entire disk is allocated as a PV, you'll likely only see an entry to /dev/md0 in "pvdisplay" 

I think "mdadm --detail /dev/md0" will give an indication of the size of the underlying MD raid1. That should be similiar to the size shown by the "pvdisplay". If the md0 is still your original 500gb, then you still need to play with mdadm until it grows. Otherwise, just grow the PV (pvresize does that) then the rest all falls into line. 

//chris

----- Original Message -----
From: "Joe Aquilina" <joeaquilina at westnet.com.au>
To: plug at plug.org.au
Sent: Thursday, 24 January, 2013 2:13:44 PM
Subject: Re: [plug] Request for advice about RAID & networking problem

At 11:27 AM 24/01/2013, you wrote:
>Hi Joe
>
>first off, does the top level filesystem support expansion (ie EXT3, 
>EXT4, XFS or something). Otherwise, copy all the data off, rebuild 
>with full capacity, use a file system that does support expansion, 
>copy it all back.

How do I find out if the top-level file system supports expansion? 
What tool will give me that info? Is that something I can find in 
fdisk output or am I looking at something else for that? Given that 
there is RAID 1 and LVM on top of that, I suspect it might be a 
combination of tools.

>then something like: (you may need google to assist, but this 
>approach generally works):
>Resize the MD disk array (mdadm grow ? or something like that)

I tried that already but it didn't seem to have any effect. Does that 
mean that the top level file system is not expandable? I tried:
mdadm --grow --size max /dev/md1
as it is that particular RAID array I want to expand.

>then resize the pv (pvresize), which I think automatically resizes 
>the VG, then you can resize the LV (lvresize) and then finally 
>resize the file system (resize2fs for EXT3, EXT4 etc, I have no 
>problems doing this with the file system online. xfs_growfs works 
>for XFS too).
>
>for the ethernet issue, if its debian, poke around in 
>/etc/udev/rules.d/70-persistent-net.rules
>
>You should see your old ethernet MAC listed in there. Delete all the 
>NIC entries and reboot, it'll fix itself. :)
>
>(probably should back up that file before editing and all if you are 
>uncomfortable, but I do that a fair bit!).
>There is a way to turn off that udev thing, I can't remember it atm. 
>:) I'm sure someone will point out a reference on how to do it. I'm 
>too lazy to open a new tab and google for it myself, right now.

Sorry, I forgot to mention that it is Debian Squeeze, v6.0.6. I seem 
to recall having to make a change in 
/etc/udev/rules.d/70-persistent-net.rules when we went through a 
similar process a year or so ago, but I forgot about that this time 
around. Will have a look in there later (the machine is offsite so I 
will have to go for a little drive later).

Thanks for the prompt response, I will let you know if I have any 
further problems on the networking side.

>:)
>
>//chris
>
>----- Original Message -----
>From: "Joe Aquilina" <joeaquilina at westnet.com.au>
>To: plug at plug.org.au
>Sent: Thursday, 24 January, 2013 11:09:51 AM
>Subject: [plug] Request for advice about RAID & networking problem
>
>Hello all.
>
>I thought I'd ask here for some advice about a RAID & networking
>problem. I am sure that there are far more knowledgeable people out
>there than me, since I am a relatively recent adoptee of Linux. Of
>course, I realise that this may not be an appropriate forum for this
>enquiry and would ask for guidance as to where I can go to get
>further assistance (other than everyone's friend Mr Google).
>
>I just had to build a new Linux box to replace an old server that was
>running on 2 old 500 Gb hard drives, running on RAID 1 and LVM. The
>new box has two 1Tb hard drives again running RAID 1 and LVM - I did
>a dd of one of the old drives and let the second drive resync from
>that. Was that a good way to go? The new machine boots and seems to
>run fine and everything seems to be there. However I am not sure of
>exactly how to get access to the extra 500Gb of space that the new
>drives provide. Any suggestion for doing this would be appreciated.
>
>The real problem is that the on-board Gigabit LAN is being seen as
>eth2 instead of as eth0 as it was on the old board. How do I "fix"
>this and get LAN/internet connectivity again? What config files do I
>need to edit and where do I go looking for them? I have never been
>great when it comes to setting up/modifying networks and am feeling
>even more out of my depth trying to do it Linux.
>
>Thanks in advance from a frustrated Linux newbie.
>
>Joe Aquilina

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Joe Aquilina                    PO Box 819 Morley WA 6943
Mobile: 0428 216069
rhadmirri at westnet.com.au  or  joeaquilina at westnet.com.au

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