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I've been having a hell of a time figuring this one out. I have an amazon linux distro running on a m1.small EC2 instance, EBS storage, and it's been working great for about 8 months. I'd like to scale this up to an m1.medium instance, however nothing I do seems to work. It always hangs with some sort of error in the system log. This error has changed from a kernel panic (before updating everything) to the following:

    Xen Minimal OS!
  start_info: 0xd27000(VA)
    nr_pages: 0xf0000
  shared_inf: 0xbf25e000(MA)
     pt_base: 0xd2a000(VA)
nr_pt_frames: 0xb
    mfn_list: 0x967000(VA)
   mod_start: 0x0(VA)
     mod_len: 0
       flags: 0x0
    cmd_line: root=/dev/sda1 ro 4
  stack:      0x946780-0x966780
MM: Init
      _text: 0x0(VA)
     _etext: 0x621f5(VA)
   _erodata: 0x76000(VA)
     _edata: 0x7b6d4(VA)
stack start: 0x946780(VA)
       _end: 0x966d34(VA)
  start_pfn: d38
    max_pfn: afffd
Mapping memory range 0x1000000 - 0xafffd000
setting 0x0-0x76000 readonly
skipped 0x1000
MM: Initialise page allocator for 12b2000(12b2000)-0(afffd000)
MM: done
Demand map pfns at afffe000-bfffe000.
Heap resides at bffff000-fffff000.
Initialising timer interface
Initialising console ... done.
gnttab_table mapped at 0xafffe000.
Initialising scheduler
Thread "Idle": pointer: 0xbffff008, stack: 0x1390000
Initialising xenbus
Thread "xenstore": pointer: 0xbffff478, stack: 0x13a0000
Dummy main: start_info=0x966880
Thread "main": pointer: 0xbffff8e8, stack: 0x13b0000
"main" "root=/dev/sda1" "ro" "4" 
vbd 2049 is hd0
******************* BLKFRONT for device/vbd/2049 **********

backend at /local/domain/0/backend/vbd/17/2049
Failed to read /local/domain/0/backend/vbd/17/2049/feature-barrier.
Failed to read /local/domain/0/backend/vbd/17/2049/feature-flush-cache.
16777216 sectors of 0 bytes

Press `ESC' to enter the menu... 2   
Press `ESC' to enter the menu... 1   
Press `ESC' to enter the menu... 0   
    [J  Booting 'Amazon Linux 2012.03 (3.2.28-45.62.amzn1.i686)'

root (hd0)

 Filesystem type is ext2fs, using whole disk

kernel /boot/vmlinuz-3.2.28-45.62.amzn1.i686 root=LABEL=/ console=hvc0 LANG=en_


initrd /boot/initramfs-3.2.28-45.62.amzn1.i686.img

close blk: backend at /local/domain/0/backend/vbd/17/2049

I've seen a bunch of posts over at the AWS dev support forum, but amazon won't give any answers unless the image being used is an amazon image. The image I'm using is an image of a machine that was using an amazon image.

I am using the same kernel (aki-407d9529), and ari is set to default. Any ideas as to what might be causing this, or how to get the contents of this server running on an m1.medium instance?

share|improve this question
I'm guessing you may have hit the 64bit vs. 32bit divide.… – ceejayoz Sep 10 '12 at 17:07
What do you mean by "ari is set to default"? – Eric Hammond Sep 10 '12 at 22:22
up vote 1 down vote accepted

Try creating an ami and then further launch a m1.medium instance from the ami you have created.
If this doesn't work try using a pv-grub aki with the instance created using the ami done in the previous step.

share|improve this answer
This got me to the solution. Apparently there are only a select few kernels that you can launch from, and not all will be available based on a number of factors (region/instance type?). It turns out that only one of the dozens of aki's that I could choose from would allow me to boot on an m1.medium instance (aki-b6aa75df). I still don't fully understand the reasons behind this, but it is now working. Thank you. – Alec Sanger Sep 12 '12 at 12:57

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