How to backup single-node docker couchDB by storing data dir?

[irinhwng]

According to documentation, I can save .couch, .shards, and shard files which all reside in /data. To test out whether all the data can be saved, I have two single-node couchDBs in two separate namespaces on openshift. For simplicity, they're called couchdb-pod1 and couchdb-pod2. Note: couchdb-pod1 has all of my dbs while couchdb-pod2 is completely empty.

Here's what I've done:

1. copy everything in /data and store it on my local machine

oc cp couchdb-pod1:/opt/couchdb/data $HOME/Desktop/data

2. once loaded, replace empty /data from couchdb-pod2 with data from step 1

oc cp /Users/me/Desktop/data couchdb-pod2:/opt/couchdb/data

Here's the issue: My original couch has x amount of records for each DB (see pic)

Once I load the data into couchdb-pod2, I'm getting the majority of the data but not all of it.

What am I doing wrong here? I don't need to touch the vm.arg file since this is single node (thats my assumption so please correct me if I'm wrong).

[big-r81]

Hi,

1. Do your pods have exact the same (CouchDB-) settings?
2. Can you check, if your copied data (after backup) has the same size of your source (pod1)?
3. Is there anything in the logs of pod2?

[irinhwng]

Thanks for the quick response. Here are my answers to your questions:

1. yes - both pods have the same settings
2. copied data size: ~528 MBs whereas the data dir in pod has ~469MBs (yes, copied data is bigger than pod data which I thought was interesting)
3. found of few notice messages but the main error I got was the following:

[error] 2023-03-10T21:07:31.568681Z nonode@nohost emulator -------- Error in process <0.19916.152> with exit value:
{database_does_not_exist,[{mem3_shards,load_shards_from_db,"_users",[{file,"src/mem3_shards.erl"},{line,400}]},{mem3_shards,load_shards_from_disk,1,[{file,"src/mem3_shards.erl"},{line,375}]},{mem3_shards,load_shards_from_disk,2,[{file,"src/mem3_shards.erl"},{line,404}]},{mem3_shards,for_docid,3,[{file,"src/mem3_shards.erl"},{line,97}]},{fabric_doc_open,go,3,[{file,"src/fabric_doc_open.erl"},{line,39}]},{chttpd_auth_cache,ensure_auth_ddoc_exists,2,[{file,"src/chttpd_auth_cache.erl"},{line,198}]},{chttpd_auth_cache,listen_for_changes,1,[{file,"src/chttpd_auth_cache.erl"},{line,145}]}]}

These questions were really helpful since they got me digging into pod2. I'm going to run this again and double-check that I don't have duplicate files in the copied directory. When I rsh'ed into pod2, I noticed the /data dir was nested (/opt/couchdb/data/data/data).

I'm having operation permissions with the cluster, so stay tuned.

[irinhwng]

*operation permission ISSUES

[irinhwng]

update: data dir was heavily nested - I tried it again with root access and every record was restored :)