# Trouble setting up incremental backup in MongoDB Cluster - Docker **URL:** \ **Category:** Percona Backup for MongoDB\ **Created:** [April 3, 2024, 1:06pm UTC](https://forums.percona.com/t/trouble-setting-up-incremental-backup-in-mongodb-cluster-docker/29529 "2024-04-03T13:06:02Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![guiguir68](https://avatars.discourse-cdn.com/v4/letter/g/ba8739/32.png) [@guiguir68](https://forums.percona.com/u/guiguir68)\ **Post date:** [April 3, 2024, 1:06pm UTC](https://forums.percona.com/t/trouble-setting-up-incremental-backup-in-mongodb-cluster-docker/29529/1 "2024-04-03T13:06:02Z")
Hello everyone, I’m currently working on setting up a new MongoDB cluster with 3 nodes for development and testing purposes. All three nodes are hosted on the same machine. I’m using Docker to run this MongoDB cluster along with containers for percona-backup-mongodb. Below is my docker-compose.yml file: ```auto version: "3" services: rs101: image: percona/percona-server-mongodb:6.0 container_name: rs101 hostname: rs101 ports: - "27017:27017" networks: - db-network command: "--port=27017 --replSet rs" rs102: image: percona/percona-server-mongodb:6.0 container_name: rs102 hostname: rs102 ports: - "28017:28017" networks: - db-network command: "--port=28017 --replSet rs" rs103: image: percona/percona-server-mongodb:6.0 container_name: rs103 hostname: rs103 ports: - "29017:29017" networks: - db-network command: "--port=29017 --replSet rs" percona-backup-mongod-1: container_name: pbm1 networks: - db-network environment: - PBM_MONGODB_URI=mongodb://pbmuser:secretpwd@rs101:27017 image: percona/percona-backup-mongodb:latest percona-backup-mongodb-2: container_name: pbm2 networks: - db-network environment: - PBM_MONGODB_URI=mongodb://pbmuser:secretpwd@rs102:28017 image: percona/percona-backup-mongodb:latest percona-backup-mongodb-3: container_name: pbm3 networks: - db-network environment: - PBM_MONGODB_URI=mongodb://pbmuser:secretpwd@rs103:29017 image: percona/percona-backup-mongodb:latest rs-init: image: percona/percona-server-mongodb:6.0 container_name: rs-init restart: "no" networks: - db-network depends_on: - rs101 - rs102 - rs103 command: > mongosh --host rs101:27017 --eval ' config = { "_id" : "rs", "members" : [ { "_id" : 0, "host" : "rs101:27017" }, { "_id" : 1, "host" : "rs102:28017" }, { "_id" : 2, "host" : "rs103:29017" } ] }; rs.initiate(config); ' networks: db-network: driver: bridge ``` At this stage, I’ve been successful in creating logical snapshot backups, which I store in a MinIO bucket: ```auto $ pbm list Backup snapshots: 2024-04-03T10:10:53Z [restore_to_time: 2024-04-03T10:11:04Z] 2024-04-03T11:49:10Z [restore_to_time: 2024-04-03T11:49:23Z] 2024-04-03T11:54:49Z [restore_to_time: 2024-04-03T11:55:00Z] 2024-04-03T11:56:48Z [restore_to_time: 2024-04-03T11:57:00Z] 2024-04-03T12:31:19Z [restore_to_time: 2024-04-03T12:31:25Z] PITR : ``` However, I’m encountering difficulties in implementing incremental backups: ```auto $ pbm backup --type incremental --base Starting backup '2024-04-03T13:00:59Z'....Backup '2024-04-03T13:00:59Z' to remote store 's3://xxxxxxxxxxxx/mongo-backup' has started $ pbm logs -s D -t 1000 2024-04-03T13:01:00Z I [rs/rs101:27017] got command backup [name: 2024-04-03T13:00:59Z, compression: s2 (level: default)] 2024-04-03T13:01:00Z I [rs/rs102:28017] got command backup [name: 2024-04-03T13:00:59Z, compression: s2 (level: default)] 2024-04-03T13:01:00Z I [rs/rs101:27017] got epoch {1712148849 3} 2024-04-03T13:01:00Z I [rs/rs102:28017] got epoch {1712148849 3} 2024-04-03T13:01:00Z I [rs/rs103:29017] got command backup [name: 2024-04-03T13:00:59Z, compression: s2 (level: default)] 2024-04-03T13:01:00Z D [rs/rs101:27017] [backup/2024-04-03T13:00:59Z] init backup meta 2024-04-03T13:01:00Z I [rs/rs103:29017] got epoch {1712148849 3} 2024-04-03T13:01:00Z D [rs/rs101:27017] [backup/2024-04-03T13:00:59Z] nomination list for rs: [[rs102:28017 rs103:29017] [rs101:27017]] 2024-04-03T13:01:00Z D [rs/rs101:27017] [backup/2024-04-03T13:00:59Z] nomination rs, set candidates [rs102:28017 rs103:29017] 2024-04-03T13:01:00Z I [rs/rs102:28017] [backup/2024-04-03T13:00:59Z] backup started 2024-04-03T13:01:00Z D [rs/rs103:29017] [backup/2024-04-03T13:00:59Z] skip after nomination, probably started by another node 2024-04-03T13:01:01Z D [rs/rs102:28017] [backup/2024-04-03T13:00:59Z] flush incremental backup history 2024-04-03T13:01:01Z D [rs/rs102:28017] [backup/2024-04-03T13:00:59Z] backup cursor id: 45d13b6e-84a5-448c-a7bf-1caca7035795 2024-04-03T13:01:04Z D [rs/rs102:28017] [backup/2024-04-03T13:00:59Z] set journal up to {1712149261 2} 2024-04-03T13:01:05Z I [rs/rs102:28017] [backup/2024-04-03T13:00:59Z] uploading data 2024-04-03T13:01:05Z D [rs/rs102:28017] [backup/2024-04-03T13:00:59Z] stop cursor polling: , cursor err: 2024-04-03T13:01:05Z I [rs/rs102:28017] [backup/2024-04-03T13:00:59Z] mark RS as error `upload data files: upload file `/data/db/journal/WiredTigerLog.0000000006`: get file stat: stat /data/db/journal/WiredTigerLog.0000000006: no such file or directory`: 2024-04-03T13:01:05Z I [rs/rs102:28017] [backup/2024-04-03T13:00:59Z] mark backup as error `upload data files: upload file `/data/db/journal/WiredTigerLog.0000000006`: get file stat: stat /data/db/journal/WiredTigerLog.0000000006: no such file or directory`: 2024-04-03T13:01:05Z E [rs/rs102:28017] [backup/2024-04-03T13:00:59Z] backup: upload data files: upload file `/data/db/journal/WiredTigerLog.0000000006`: get file stat: stat /data/db/journal/WiredTigerLog.0000000006: no such file or directory 2024-04-03T13:01:05Z D [rs/rs102:28017] [backup/2024-04-03T13:00:59Z] releasing lock 2024-04-03T13:01:05Z D [rs/rs101:27017] [backup/2024-04-03T13:00:59Z] bcp nomination: rs won by rs102:28017 2024-04-03T13:01:05Z D [rs/rs101:27017] [backup/2024-04-03T13:00:59Z] skip after nomination, probably started by another node ``` Specifically, I’m unable to generate incremental backups. While I can locate the file /data/db/journal/WiredTigerLog.0000000006 on one of the MongoDB nodes (rs103), I can’t seem to find it on the other nodes. Here is the actual PBM status: ```auto $ pbm status Cluster: ======== rs: - rs/rs101:27017 [P]: pbm-agent v2.4.1 OK - rs/rs102:28017 [S]: pbm-agent v2.4.1 OK - rs/rs103:29017 [S]: pbm-agent v2.4.1 OK PITR incremental backup: ======================== Status [ON] Currently running: ================== (none) ``` and the backup config: ```auto storage: type: s3 s3: endpointUrl: "http://xxxxxxxxxx" region: us-east-1 bucket: mongo-backup credentials: access-key-id: xxxxxxx secret-access-key: xxxxxxx ``` I’m wondering if anyone could shed some light on what might be going wrong or if there’s something I might have missed in the setup process. Thank you in advance for your help and suggestions! ---
**Author:** ![Vicenc\_Juan\_Tomas\_Mo](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/vicenc_juan_tomas_mo/32/16477_2.png) [@Vicenc\_Juan\_Tomas\_Mo](https://forums.percona.com/u/Vicenc_Juan_Tomas_Mo)\ **Post date:** [May 17, 2024, 9:16am UTC](https://forums.percona.com/t/trouble-setting-up-incremental-backup-in-mongodb-cluster-docker/29529/2 "2024-05-17T09:16:26Z")
PBM needs to have access to the MongoDB data files. So, you need to mount the MongoDB datadir volume into the pbm containers. ---
**Author:** ![Ivan\_Groenewold](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/ivan_groenewold/32/6299_2.png) [@Ivan\_Groenewold](https://forums.percona.com/u/Ivan_Groenewold)\ **Post date:** [May 17, 2024, 12:24pm UTC](https://forums.percona.com/t/trouble-setting-up-incremental-backup-in-mongodb-cluster-docker/29529/3 "2024-05-17T12:24:05Z")
Hi, for physical backups (required for incremental) the pbm agent container needs to be able to access the files of the mongod container. I think you will need to use either a bind mount or shared volume for storage.