Trying to use the Docker API to create/stop/delete a container gives the error
client version 1.43 is too new. Maximum supported API version is 1.41
Use the following
export DOCKER_API_VERSION=1.41
as described here
There is a newer way of using the command, as it is also the case in a few other docker commands.
Even though both the command can be used to remove a docker image, the command using docker image rm is the most recent way of using it.
Trying to start the docker service after some upgrades fails with the following message:
Failed to start docker.service: Unit is masked.
It turns out that after upgrading or more specifically removing and then upgrading the docker installation in ubuntu (in this particular case in raspberry 4 with Ubuntu 20.04 installed), results in this error.
A search brings up the following:
https://forums.docker.com/t/failed-to-start-docker-service-unit-is-masked/67413
and from that the following bug post:
https://bugs.launchpad.net/ubuntu/+source/docker.io/+bug/1844894
So the solution is to run the following to be able to start the docker service (described in the first link above):
sudo systemctl unmask docker sudo systemctl start docker
You would like to test worldPing (https://worldping.raintank.io/worldping/) in your local environment for evaluation purposes.
$ docker exec -it grafana /bin/bash bash-5.0$ grafana-cli plugins install raintank-worldping-app
bash-5.0$ exit $ docker stop grafana $ docker start grafana
You wold like to know the IP Address of your host from inside a running docker container.
Run the following inside the container:
route | awk '/^default/ { print $2 }'
Problem
You are trying to use docker-compose to get some services up with docker but you see an error like the following:
Cannot create container for service xxx: invalid mode: /path/to/volume/
Solution
This is more than likely caused by a typo in your yml file, so go back and check carefully for any typos and correct them.
Problem
Using docker-compose up (or build), displays the following error message (even though the same command used to work previously):
ERROR: Couldn't connect to Docker daemon at http+docker://localunixsocket - is it running?
Solution
This is quite possible caused by permissions issue, as one of the folders files that docker is trying to use is owned by a different user/group from the one trying to use the docker-compose commands. Try to find the file/folder with the different permissions and change it to your user name and group, or use change the files by using something like:
chown -R me:me .
Problem
You are trying to run the ps command in a docker container (ie ps ax), but you get:
bash: ps: command not found
Solutionapt install procps
Taken from the answer here
Problem
You would like to know the IP Address of a running Docker container.
Solution
Use the following to find out the IP Address by replacing the container_name with the actual container name:
docker inspect -f '{{ .NetworkSettings.IPAddress }}' container_name
Problem
You are trying to set up http endpoint monitoring with prometheus and blackbox_exporter by specifying something like the following:
...
job_name: 'blackbox'
metrics_path: /probe
params:
module: [http_2xx]
static_configs:
- targets:
- 'localhost:8080'
relabel_configs:
- source_labels: [__address__]
target_label: __param_target
- source_labels: [__param_target]
target_label: instance
- target_label: __address__
replacement: 127.0.0.1:9115
...
but you are getting the error (in prometheus targets) that connection was refused.
Solution
First specify the ip protocol as ip4 if you are not using ip6 like:
modules:
http_2xx:
prober: http
timeout: 5s
http:
preferred_ip_protocol: "ip4"
valid_status_codes: [200]
method: GET
And then make sure that you use the container IP address in the replacement field if you have started blackbox_exporter as a docker container (tip taken from here), which you can find by looking for the container IP address (docker inspect blackbox_exporter | grep IPAddress).
So your prometheus configuration should look like the following (different replacement IP):
job_name: 'blackbox'
metrics_path: /probe
params:
module: [http_2xx]
static_configs:
- targets:
- 'localhost:8080'
relabel_configs:
- source_labels: [__address__]
target_label: __param_target
- source_labels: [__param_target]
target_label: instance
- target_label: __address__
replacement: 172.17.0.3:9115