Failed to find one of the right cookies. Core dumped

[hashmap]

Grin was running when my server was rebooted. After that any attempt to start grin failed with the message above. Removal of chain_data helped.

[hashmap]

I found it's croaring https://github.com/RoaringBitmap/CRoaring/blob/master/src/roaring_array.c#L767

[antiochp]

We corrupted one of the pmmr_leaf.bin or pmmr_prun.bin files somehow? We were writing to one of those when the server rebooted?

Oof.

[sesam]

was this before or after antioch's fix for safely writing files before stopping grin?

[antiochp]

My fix won't help with a server reboot, only on "clean" shutdown via the grin node itself.

[sesam]

ok. is core dumping risking spilling secrets to disk? should we catch this, show a warning, then either shut-down gracefully, or somehow retry?

[hashmap]

Saw another report in gitter. I predict it may be a problem when we get enough nodes.

[ignopeverell]

Good prediction. One issue I think is that on other storages (LMDB, MMRs), we have a way to get back to a previous snapshot (the chain head) so if a write didn't really work out we can easily find a workable checkpoint. It doesn't seem as easy with croaring but might not be too hard to add?

[antiochp]

Just so there is no confusion here - there is zero persistence in the croaring library, all of this is on us, we literally just write the bytes to a file. I believe we use a temp file to make things reasonably atomic but we have not put a lot of thought into doing this really robustly.

[hashmap]

Memory-mapped file could help, unfortunately it's not yet supported by croaring (but supported by java and go versions) https://github.com/RoaringBitmap/CRoaring/issues/74

[TheJimmyH]

Was there ever a resolution to this? I just ran an Nvidia graphics driver update on my PC. Somewhere during the update, it crashed my Virtual Box machine, which was running my node. Now, I am unable to restart my node..

Is there a workaround to get this back up and running, or should I destroy this machine, make a new one, and import the old wallet?

[hashmap]

@Jimmy24651 sure, the workaround is in the issue text, rm -rf ~/.grin/main/chain_data (replace main with floo for floonet)

[0xmichalis]

@hashmap is this an issue anymore?

[hashmap]

@kargakis I think it's still an issue, a server could be stopped abruptly by power outage or the process be killed by kill -9 etc

[niahmiah]

Issue still exists on grin 2.0.0

[madmarks]

I have a node installed on my mining rig because of solo mining and after every third power outage I have to do rm -rf ~/.grin/main/chain_data and download the whole blockchain again. Very annoying bug.

[BLOCKCHAINSMOKER]

Issue still exists on grin 3.0. The power went out on my computer and I recieved the following error when I tried to restart grin 'I failed to find one of the right cookies. Found 3497651248 Segmentation fault (core dumped)' Is there a fix for this? I tried 'rm -rf ~/.grin/main/chain_data' and i still get the same error.