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Created May 24, 2019 14:48
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cirros debug and use
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README.md

Cirros Debug and usage

Boot to initramfs only

Cirros has kernels and initramfs available for many arch. Sometimes you might just need to boot a kernel and look around, but not on a cloud.

It was intended that using 'dslist=none' on the kernel command line would do that, but a logic bug prevented it, you can still get this to work though with 0.4.0.

qemu-system-x86_64 -nographic -m 512 \
    -kernel cirros/kernel  -initrd cirros/initrd \
    -append "console=ttyS0 dslist=true rdroot"

There:

  • rdroot: flag instructs cirros explicitly to run from intiramfs.
  • dslist=true tricks the bug in cirros to run the 'true' (/bin/true) datasource.

That will boot you into a cirros that runs entirely from the initramfs. Log in with 'cirros' and 'gocubsgo'.

init=/bin/sh

As standard linux, you can pass the kernel command line 'init=/bin/sh'

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