I use PBM 2.3.1, backup from mongodb community 4.4.19 and I tried to restore it to mongodb community 4.4.6.
My mongodb cluster structure: sharded cluster with one shard (cfg - config servers and rs0 - replica set with data).
During restore I got an error on pbm-agent on cfg (config server):
Mar 13 09:27:52 mongo-config-temp-1 pbm-agent[270150]: 2024-03-13T09:27:52.000+0300 E [restore/2024-03-12T09:17:57.06870632Z] restore: reply oplog: replay chunk 1709980427.1709981056: apply oplog for chunk: applying an entry: op: {“Timestamp”:{“T”:1709980453,“I”:5},“Term”:12,“Hash”:null,“Version”:2,“Operation”:“i”,“Namespace”:“config.actionlog”,“Object”:[{“Key”:“_id”,“Value”:“mongo-gridfs-config-2:27019-2024-03-09T13:34:13.373+03:00-65ec3b253b19dc09291bb708”},{“Key”:“server”,“Value”:“mongo-gridfs-config-2:27019”},{“Key”:“shard”,“Value”:“config”},{“Key”:“clientAddr”,“Value”:“10.141.83.141:37272”},{“Key”:“time”,“Value”:“2024-03-09T10:34:13.373Z”},{“Key”:“what”,“Value”:“balancer.start”},{“Key”:“ns”,“Value”:“”},{“Key”:“details”,“Value”:[]}],“Query”:null,“UI”:{“Subtype”:4,“Data”:“vKBQhWnQTO2CY0WzxfgUkg==”},“LSID”:null,“TxnNumber”:null,“PrevOpTime”:null} | merr : applyOps: (NamespaceNotFound) Failed to apply operation due to missing collection (bca05085-69d0-4ced-8263-45b3c5f81492): { ts: Timestamp(1709980453, 5), t: 12, v: 2, op: “i”, ns: “config.actionlog”, o: { _id: “mongo-gridfs-config-2:27019-2024-03-09T13:34:13.373+03:00-65ec3b253b19dc09291bb708”, server: “mongo-gridfs-config-2:27019”, shard: “config”, clientAddr: “10.141.83.141:37272”, time: new Date(1709980453373), what: “balancer.start”, ns: “”, details: {} }, ui: UUID(“bca05085-69d0-4ced-8263-45b3c5f81492”), h: 0, wall: new Date(0) }
After this error, the recovery process on rs0 (data) continued and was completed successfully:
Mar 13 17:02:56 mongo-temp-1 pbm-agent[224615]: 2024-03-13T17:02:56.000+0300 I [restore/2024-03-12T09:17:57.06870632Z] recovery successfully finished
Why did the error occur on the cfg? The config.actionlog collection is there.