Arch Linux

Dusty

Schwag Merchant

From: Medicine Hat, Alberta, Canada

Registered: 2004-01-18

Posts: 5,986

Website

xen Amazon EC2 instance won't serialize -- /dev/loop doesn't exist

Hey all,

I've been doing a bunch of tweaking on an Amazon EC2 instance running Arch Linux. Now its almost perfect... but when I run ec2-bundel-vol it dies.

mount: could not find any device /dev/loop#
execution failed: "mount -o loop /mnt/image /mnt/img-mnt"
ec2-bundle-vol failed.

Ok, so there's no loopback. modprobe loop, that'll fix it right?

root:~ # modprobe loop
FATAL: Could not load /lib/modules/2.6.16-xenU/modules.dep: No such file or directory

OOPS. That kernel that's running isn't the arch kernel (The installed kernel26 is 2.6.26) -- which, after it happened, made perfect sense. It must be the parent kernel on the XEN machine. Ok, I'll bite, how the hell does that work?

lsmod turns up empty; I don't know if its querying the XEN kernel or the Arch kernel. /proc/modules is also empty.

I thought I had EC2 fully figured, but this has thrown me for a loop (no pun intended). I don't know much about how xen works, so I'm kind of stuck.

Is there a chance I can create the loopback device without modprobing it; I'd assume the parent kernel has the module loaded but the device didn't get created. What would be the procedure for that?

Thanks for any insight.

Dusty

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byte

Member

From: Düsseldorf (DE)

Registered: 2006-05-01

Posts: 2,046

Re: xen Amazon EC2 instance won't serialize -- /dev/loop doesn't exist

mknod /dev/loop0 b 7 0

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1000

Dusty

Schwag Merchant

From: Medicine Hat, Alberta, Canada

Registered: 2004-01-18

Posts: 5,986

Website

Re: xen Amazon EC2 instance won't serialize -- /dev/loop doesn't exist

Would that work even if the loop module isn't loaded in the kernel?

I did some study on xen last night and I discovered that host systems run a custom kernel that is then propagated to guest systems. So I took a chance and copied the modules for the xen kernel from an Ubuntu EC2 instance. After that I was able to insmod loop.ko and proceed with serializing my new AMI. I have a feeling this isn't the correct thing to do, but it got me out of a pinch.

Dusty

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** Arch Linux Apparel and more ** Arch Linux stickers, laptop bags, jewelery ** I wrote a book on Python 3 ** and one on mental health **