os-prober with many zvols/snapshots makes upgrades painful

[pdf]

I store VMs on zvols, and use zfs-auto-snapshot to provde point-in-time rollback. As a result, I current have ~1400 /dev/zd* device nodes. The result is horrendous behaviour from os-prober at kernel/grub update, since it tries to mount them all.

My current hack-around is just to patch /usr/bin/os-prober ignore devs with major 230, but I'm open to more sensible options if anyone has any. I do think os-prober is going to need patching though...

[dajhorn]

There might be a way to avoid patching os-prober because this logic is in the /etc/grub.d/30_os-prober file:

OSPROBED="`os-prober | tr ' ' '^' | paste -s -d ' '`"
if [ -z "${OSPROBED}" ] ; then
  # empty os-prober output, nothing doing
  adjust_timeout
  exit 0
fi

Installing a dummy test to /usr/lib/os-prober that emits an empty result for zvols could short the os-probe test series.

[pdf]

Installing a dummy test to /usr/lib/os-prober that emits an empty result for zvols could short the os-probe test series.

Good call, here's what I'm using now (/usr/lib/os-probes/10zvol-test):

#!/bin/sh
# Sub-test to exclude ZVOLs
set -e
partition="$1"

. /usr/share/os-prober/common.sh

if [ "$(stat -L -c %t "$partition")" = "e6" ] ; then
        debug "$1 is a ZVOL; skipping"
        exit 0
fi

# No ZVOLs found
exit 1

[dajhorn]

I added this test and credited you.

[pdf]

Thanks Darik

[pdf]

On small change required - this needs to be chmod'd +x

[dajhorn]

Thanks. I squeaked it into rc13.