Struggling noob with docker

[luckman212]

Hi and please forgive me in advance if these are foolish questions.

I found Gatus and really want to set it up in my homelab. So, off I went, to install Ubuntu20 + Docker and fumble my way through getting the thing running. I guess the installation guide assumes a good working knowledge of docker, kubernetes, helm, etc. Guess I'll need to really study up on that.

Relevant xkcd: https://xkcd.com/1988/

Anyway, I figured out how to install the docker image such that it auto-starts on boot:

docker volume create gatus-storage

docker run -d --restart unless-stopped -p 8080:8080 --name=gatus -v gatus-storage:/var/lib/gatus twinproduction/gatus

The problem is, I also want to enable sqlite storage, and can't figure out how to do that. I saw the example at https://github.com/TwinProduction/gatus/tree/master/examples/docker-compose-sqlite-storage, and I figured I could copy the docker-compose.yml to e.g. /root/gatus/docker-compose.yml and then run docker-compose up to get it running (but not as a daemon). (Trying to figure out how to access the gatus-storage volume created above to edit the config.yaml contained within).

I tried this command, but it dies immediately:

# docker run -p 8080:8080 --mount type=bind,source=/root/gatus/config.yaml,target=/config/config.yaml --name gatus twinproduction/gatus
2021/08/23 00:37:59 [config][Load] Reading configuration from configFile=config/config.yaml
2021/08/23 00:37:59 [config][validateAlertingConfig] Alerting is not configured
2021/08/23 00:37:59 [config][validateServicesConfig] Validated 2 services
2021/08/23 00:37:59 [storage][Initialize] Creating storage provider with type=sqlite and file=/data/data.db
panic: unable to open database file: out of memory (14)

goroutine 1 [running]:
main.main()
    /app/main.go:19 +0x165

Is this supposed to be easier?

Another possibly unrelated issue is, I have a simple ICMP test, running at 10s intervals. The Average Response Time graph at the bottom does not seem to update, and also does not seem to correlate at all with the gathered data.

e.g. screenshot taken at 8:31pm... 🤷‍♂️

Again, I'm sure most of this is just me being ignorant, and for that I apologize. Thank you for any guidance.

[TwiN]

Hello @luckman212,

Don't worry, there are no foolish questions :)

Regarding your question on using Gatus with SQLite storage, what happens if you clone gatus and docker-compose up from the examples/docker-compose-sqlite-storage folder? I suspect that due to not having a data folder where you copied the docker-compose.yml file, you're running into some issues.

git clone https://github.com/TwinProduction/gatus
cd gatus/examples/docker-compose-sqlite-storage
docker-compose up

As for the chart, it's a brand new feature, so it might have some bugs, but here's what I think might answer some of your questions:

• The chart is generated on the server side, which might be why the time doesn't match 😅
• The chart represents the average over the past 24 hour, and it does not currently automatically update (good catch! I just created #162 to address that issue)
• The reason why it's showing 2 instead of 3, despite the fact that ~3ms is displayed in the corner could be explained by two things:
  • The graph does not refresh automatically, so you might be seeing an older average.
  • The ~3ms displayed is only the average of every check visible in the bar above, which is to say the past 20 checks, or over the past 3 minutes in your case. So it might make sense for the hourly average to not be the same as the average over the past 20 checks.

[luckman212]

Thanks for the help @TwinProduction - I tried cloning the git repo and running the example directly (it works 👍 )

I see the data.db that gets created seems persistent. So I am still very cloudy and hazy about how the container storage works (volumes, temp filesystems, etc). That isn't directly an issue with Gatus of course, just my ignorance of how Docker works.

Thank you for opening #162

I will continue banging my head against this hard surface until it clicks into place.

[TwiN]

Hahaha good luck, then!

I'll close this in the meantime, but if you have any questions, don't hesitate to ask.