Backing up Discourse with RDS

| community | devops | aws |

We are launching a community site with Discourse at CircleCI and I ran into some issues with performing backups.

Since we want to be #webscale, rather than installing Discourse using the easy Docker method, we opted to split up the services on AWS.

We are using EC2, RDS, ElasticCache, ELB and S3 for backups. When I initially launched PostgreSQL on RDS I just picked the latest version (9.4 at time of writing) and didn’t put much thought into it. The problem is that the version of pg_dump inside the Docker container provided by Discourse is 9.3.  Apparently you are not able to do a pg_dump when your client and server are mismatched.

When you try to do this, you get a sad error that states:

aborting because of server version mismatch

In order to fix this, we need to upgrade the client version on the Docker container (or alternatively avoid this all together by using the same version of PostgreSQL on RDS). Since it is easier to update the client than downgrade RDS, I opted to upgrade the client.

To do this:

  1. Log into the EC2 Instance that is running Discourse
  2. Go to the Discourse install location (mine is in /var/docker)
  3. Enter the container with:
    sudo ./launcher enter app
    
  4. Upgrade the version of PostgreSQL client
    apt-get install postgresql-9.4
    
  5. Swap out the pg_dump symbolic link for the newer version
        ln -s /usr/lib/postgresql/9.4/bin/pg_dump /usr/bin/pg_dump
    
  6. Perform your  backup
When you update the Docker container for the next release you will likely have to repeat these steps until Discourse gets to the same version of PostgreSQL as the one you chose on RDS.

Thank you for reading! Share your thoughts with me on mastodon or via email.

Check out some more stuff to read down below.

Most popular posts this month

Recent Favorite Blog Posts

This is a collection of the last 8 posts that I bookmarked.

Articles from blogs I follow around the net

Supermicro NVIDIA GB200 NVL72 System at Computex 2024

We checked out the Supermicro NVIDIA GB200 NVL72 rack at Computex 2024. This is a prime example of why power is becoming such a big deal The post Supermicro NVIDIA GB200 NVL72 System at Computex 2024 appeared first on ServeTheHome.

via ServeTheHome July 22, 2024

Forum

Community is one of the main topics I touch on here. My community, my social media is an email and iMessage, but I thought I could do more. I did such an experiment last year and I quit soon after. I don't think I was ready for it. Today I still don&#…

via Michal Zelazny July 21, 2024

Weekly Update 409

It feels weird to be writing anything right now that isn't somehow related to Friday's CrowdStrike incident, but given I recorded this video just a few hours before all hell broke loose, it'll have to wait until next week. This week, the issue…

via Troy Hunt July 21, 2024

Generated by openring