Open kanyi opened 1 year ago
is this is related to #313?
Yes. cAdvisor can create more detailed statistics for containers, but yes, basically the same.
I'd like to avoid using third party tools that might be difficult to install in all systems. I mean, I'd prefer using podman
to get the statistics.
In this aspect, and as I already said in #313, I'm not familiarized with podman
or containers in general. So, I'm pretty lost when trying to get stats of running containers using the root
user, when the containers are being ran using another user (which will be the common case).
Can you, please, share a list of useful commands that Monitorix can run to get general container statistics?
That would get me an idea to develop the new module container.pm
.
Sorry but I don't use podman until now. I wil check it, and figure out these command is working or not. But, maybe this is help for you.
The normal docker stat
command but separated the values:
docker stats --format "table {{.Container}}\t{{.Name}}\t{{.CPUPerc}}\t{{.MemUsage}}\t{{.NetIO}}\t{{.BlockIO}}\t{{.MemPerc}}\t{{.PIDs}}"
The last 2 values (MemPerc and PIDs) works only linux systems.
The trick about running docker
command, under linux you have a GID name is docker
, not only a user. So every user who is in these docker
group can run all of the docker commands without any other privileges. I your case, under linux, the monitorix
user is added to docker
group you can read the stats and run docker commands.
As I read it, podman
and docker
are very similar tools, they share almost the same options and syntax. Moreover, I discovered that I can install the package podman-docker
on Fedora to emulate Docker CLI using Podman.
So, I just ran your command and I got the following:
$ docker stats --format "table {{.Container}}\t{{.Name}}\t{{.CPUPerc}}\t{{.MemUsage}}\t{{.NetIO}}\t{{.BlockIO}}\t{{.MemPerc}}\t{{.PIDs}}"
<no value> NAME CPU % MEM USAGE / LIMIT NET IO BLOCK IO MEM % PI DS
Error: template: stats:1:13: executing "stats" at <.Container>: can't evaluate field Container in type containers.containerStats
$
No stats.
Then I checked the processes with containers using docker
and I see the same output as with podman
:
$ docker ps -a
Emulate Docker CLI using podman. Create /etc/containers/nodocker to quiet msg.
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
6725ce9cb235 docker.io/library/busybox:latest sh About an hour ago Exited (0) 51 minutes ago compassionate_bose
$
Looks podman can not recognize the {{.Container}} variable. - That's true https://docs.podman.io/en/latest/markdown/podman-stats.1.html So here is a difference, in docker and podman. :-)
I think this work, under podman (this is working for me Debian 11, Docker 20.10):
You can leave the table
this is only for headers.
docker stats --format "{{.ID}}\t{{.Name}}\t{{.CPUPerc}}\t{{.MemUsage}}\t{{.NetIO}}\t{{.BlockIO}}\t{{.MemPerc}}\t{{.PIDs}}"
Still no stats.
Moreover, the command does not return. It keeps refreshing which ruins the chance to get stats.
Monitorix runs under the root
user, if that user cannot get Docker/Podman generic (all users) stats then this will be hard to implement.
For me, the root user can run a docker stats
command without any problem.
For you maybe podman stats -a --no-stream
?
Oh, and Docker has an API interface, more detailed statistics. In this case you have to know the container ID, but I don't think is a problem monitoring only the given ID's and not all of the containers.
Access API information as follows for a JSON stream in every second:
curl -v --unix-socket /var/run/docker.sock \ http://localhost/containers/CONTAINER_ID/stats
Substitute CONTAINER_ID with the actual ID of the container being inspected.
But in this case you have a "little" more work: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/building_running_and_managing_containers/assembly_using-the-container-tools-api_building-running-and-managing-containers
cAdvisor as datasource. That will be a big help of monitoring containers in Monitorix.