Docker

RabbitMQ is not persisting messages despite using Docker volumes

Docker will create a randomly generated hostname for each container every time you deploy a new container instance.

RabbitMQ stores persistent message/queue data using a folder structure based off a node’s hostname. If you do not set a static container hostname, then RabbitMQ will loose any unprocessed messages if you launch a new RabbitMQ container or do a docker-compose down/up.

This happens even if you use a persistent volume (docker run -v).

This will result in tasks being lost and may be the reason a document has not been OCR’d or processed completely.

Solution: Ensure you run the RabbitMQ container with the --hostname option when starting, ensuring RabbitMQ uses a static folder name every time it starts, such as:

docker run -d --name mayan-rabbitmq --hostname mayan-rabbitmq --restart=always...

For Docker Compose:

rabbitmq:
    container_name: mayan-edms-rabbitmq
    image: rabbitmq:3-management
    hostname: mayan-edms-rabbitmq
    environment:
    RABBITMQ_DEFAULT_USER: mayan
    RABBITMQ_DEFAULT_PASS: mayanrabbitpass
    RABBITMQ_DEFAULT_VHOST: mayan
    networks:
    - mayan-bridge
    restart: unless-stopped
    volumes:
    - /docker-volumes/mayan-edms/rabbitmq:/var/lib/rabbitmq

References: - https://stackoverflow.com/questions/41330514/docker-rabbitmq-persistency

MAYAN_APT_INSTALLS does not work for Archlinux with kernels > 4.14

This is caused by a change from kernel 4.18 - 4.19. Metacopy on these kernels is set to yes in archlinux kernels (/sys/module/overlay/parameters/metacopy) and overlayfs should override this which it does not at the moment.

The workaround is to disable metacopy:

echo N | sudo tee /sys/module/overlay/parameters/metacopy

References:

Error: IOError: [Errno 37] No locks available when using a NFS volume for MAYAN_MEDIA_ROOT

This is caused by an upstream Django issue and occurrs when using a NFS volume for MAYAN_MEDIA_ROOT. File lock issues can prevent Mayan from generating the static media inside MAYAN_MEDIA_ROOT.

If you’re using NFSv3, ensure that rcp.statd is running on the NFS client (called nfs-lock on some distributions) and that no_auth_nlm is set in /etc/exports on the NFS Server. NFSv4 has locking built in so does not require rcp.statd, but may require no_auth_nlm set on the NFS Server.

A workaround if the issue persists after applying the above is to deploy Mayan with a NFS MAYAN_MEDIA_ROOT with a local-only volume for MAYAN_MEDIA_ROOT/static. An example volume section inside docker-compose:

volumes:
# $MAYAN_MEDIA_ROOT can be mounted to nfs and shared between nodes. Change /mnt/mayan-shared
# to the path of the mounted NFS export
- /mnt/mayan-shared/media:/var/lib/mayan

# $MAYAN_MEDIA_ROOT/static must be local to avoid locking issues
- /docker-volume/static:/var/lib/mayan/static

# Other mounts (such as watch folder). Must be on a different NFS export to avoid lock issues
- /mnt/watch:/srv/watch_folder

Alternatively, you can use non-NFS backed volumes for the whole MAYAN_MEDIA_ROOT share where no local static directory is required. Samba and iSCSI are known to work.

References: