Error occurred after transferring docker images to another device.

[Mojy0715]

I am trying to transfer docker image built from my laptop to another computer without internet connection.

The way I have done it:

1. Building the image on my laptop.
2. docker save to get the .tar file of the image
3. Copy the .tar file into a USB flash drive
4. Connect USB flash drive and copy the .tar file to the other computer without internet connection
5. docker run image
6. docker exec -it [CONTAINER ID] psql -U postgres (I have not changed any config, other than setting either POSTGRES_PASSWORD=password or POSTGRES_HOST_AUTH_METHOD=trust for testing)

and I got psql: error: connection to server on socket "/var/run/postgresl/.s.PGSQL.5432" failed: FATAL: could not find tuple for opclass 1981. The postgres container running on my laptop is working fine.

docker logs does not show anything particular:

PostgreSQL Database directory appears to contain a database; Skipping initialization

2024-03-04 08:07:24.039 UTC [1] LOG:  starting PostgreSQL 15.6 (Debian 15.6-1.pgdg120+2) on x86_64-pc-linux-gnu, compiled by gcc (Debian 12.2.0-14) 12.2.0, 64-bit
2024-03-04 08:07:24.039 UTC [1] LOG:  listening on IPv4 address "0.0.0.0", port 5432
2024-03-04 08:07:24.039 UTC [1] LOG:  listening on IPv6 address "::", port 5432
2024-03-04 08:07:24.046 UTC [1] LOG:  listening on Unix socket "/var/run/postgresql/.s.PGSQL.5432"
2024-03-04 08:07:24.054 UTC [29] LOG:  database system was shut down at 2024-03-04 06:54:42 UTC
2024-03-04 08:07:24.061 UTC [1] LOG:  database system is ready to accept connections
2024-03-04 08:07:35.052 UTC [40] ERROR:  could not find tuple for opclass 1981

also I installed docker & docker compose on the computer without internet connection through dpkg -i with the packages I got from https://download.docker.com/linux/ubuntu/dists/jammy/pool/stable/amd64/

Please do enlighten me. Thank you.

[LaurentGoderre]

I think it probably would be better to treat postgres container as ephemeral and use postgres data export functions to move the data to a new container.