cbrestore/cbbackup from Couchbase 5.5 to Couchbase 6.5 - couchbase

Question

I have backed up data from an Couchbase 5.5 cluster, using the following command:
$ cbbackup http://couchbase:8091 ~/cbbackup -u *** -p ***
Then, I copied the ~/cbbackup files out of the cluster and onto my local machine.
I have a new Couchbase 6.5 cluster that I want to migrate the data to.
So then I copied ~/cbbackup in to the new cluster.
However, when I try to restore it in the Couchbase 6.5 cluster this happens:
$ cbrestore ~/cbbackup http://couchbase:8091 -u *** -p ***
2020-05-23 14:11:47,209: s0 error: async operation: error: conn.sendall() exception: [Errno 104] Connection reset by peer on sink: http://couchbase:8091(b'default'#b'couchbase-0001.couchbase.couchbase.svc:8091')
2020-05-23 14:11:47,221: s2 error: async operation: error: conn.sendall() exception: [Errno 104] Connection reset by peer on sink: http://couchbase:8091(b'default'#b'couchbase-0003.couchbase.couchbase.svc:8091')
2020-05-23 14:11:47,226: s1 error: async operation: error: conn.sendall() exception: [Errno 104] Connection reset by peer on sink: http://couchbase:8091(b'default'#b'couchbase-0002.couchbase.couchbase.svc:8091')
error: conn.sendall() exception: [Errno 104] Connection reset by peer
How can I restore the backup from Couchbase 5.5 to my Couchbase 6.5 cluster?

Answer 1

Luckily, I know exactly what you need!
According to this chart of version compatibility, it should be possible for Couchbase 6.5 to restore backups from all the way back to Couchbase 5.0.
The reason it's failing though, I'm not sure. According to this thread at the Couchbase forums, it could be because of some problem handling xattrs [MB-31224] made by Sync Gateway; but again, I'm not sure.
However, after much trial and error, what worked for me once was to use cbbackup from 6.5 to make a backup of the 5.5 cluster. Then it's not cbbackup from 5.5 and cbrestore from 6.5, but rather both from 6.5. And it worked!
My setup was running in Kubernetes, so I did something like this:
$ kubectl run -i -t couchbase-migrate --image=couchbase/server:6.5.1 --restart=Never --rm=true --command -- /bin/bash
root#couchbase-migrate:/# cbbackup http://couchbase:8091 ~/cbbackup -u *** -p ***
...
Then I copied the backup out of the couchbase-migrate pod and onto my local machine.
After that, I did the restore similarly:
$ kubectl run -i -t couchbase-migrate --image=couchbase/server:6.5.1 --restart=Never --rm=true --command -- /bin/bash
...
root#couchbase-migrate:/# cbrestore ~/cbbackup http://couchbase:8091 -u *** -p ***
...

Answer 2

There are compatibility issues with the backup and restore process among the various Couchbase versions.
From the problem statement, it seems like it's one time data migration.
If nothing works and actually I too had the similar use cases, where I simply exported all the records from older version of Couchbase to a external file by running the simple SELECT query and ingested the same using the simple java based application to later version of Couchbase.
The difference between this approach and standard backup/restore process is, backup/restore would take care of building the indexes also and will be faster too.