Recovering lost data » History » Revision 2
Revision 1 (Tom Clegg, 04/25/2019 03:16 PM) → Revision 2/7 (Nico César, 04/26/2019 06:32 PM)
h1. Untrashing lost blocks
In some cases it is possible to recover data blocks that have been trashed by keep-balance (due to a bug or an install/config error).
If you suspect blocks have been trashed erroneously, you should immediately:
# On all keepstore servers: set EmptyTrashInterval to a long time like 2400h
# On all keepstore servers: restart keepstore
# Stop the keep-balance service
When you think you have corrected the underlying problem, you should:
# Set LostBlocksFile to a suitable value (perhaps "/tmp/keep-balance-lost-blocks.txt") in your keep-balance config
# Start keep-balance
After keep-balance completes its first sweep, inspect /tmp/keep-balance-lost-blocks.txt. If it's not empty, you can request all keepstores to untrash any blocks that are still recoverable with a script like this:
<pre><code class="bash">
#!/bin/bash
set -e
# see Client.AuthToken in /etc/arvados/keep-balance/keep-balance.yml
token=xxxxxxx-your-system-auth-token-xxxxxxx
# all keep server hostnames
hosts=(keep0 keep1 keep2 keep3 keep4 keep5)
while read hash; do
echo "${hash}"
for h in ${hosts[@]}; do
if curl -fgs -H "Authorization: Bearer $token" -X PUT "http://${h}:25107/untrash/$hash"; "http://${host}:25107/untrash/$hash"; then
echo "${hash} ok ${host}"
fi
done
done < /tmp/keep-balance-lost-blocks.txt
</code></pre>