Debugging containers that have no shell (opens in new tab)

(docs.docker.com)

31 pointspploug4mo ago7 comments

7 comments

pplougOP4mo ago

Docker Debug was previously a paid-for feature, now available for free since v4.49

Please note the analogous mechanism on kubernetes ("ephemeral containers") works only with the pod's shareProcessNamespace: true setting, which is usually off. So you won't be able to do this out of the box with your deployment already running on a typical stack

dixie_land4mo ago

this is not true, `kubectl debug` attaches to the namespace of a container of your choosing (`--target` argument). You don't have to enable process namespace sharing at the pod level

kunley4mo ago

Last time I've checked, kubectl debug would not attach if namespace sharing wasn't enabled in the first place. Has it changed? What k8s version are you using?

PS. Even without checking again, it would be surprising if it changed. Even the official documentation is mentioning that this is needed

benterix4mo ago

Does podman contain or plan to implement something similar? Seems very useful.

kitd4mo ago

Not that I could find. There is always the option to use a sidecar container, eg:

https://matthewsanabria.dev/posts/no-shell-for-you-container...

https://iximiuz.com/en/series/mastering-container-debugging/

pella4mo ago

Only for "Docker Desktop 4.49 and later"

j / k navigate · click thread line to collapse

7 comments

pplougOP4mo ago

Docker Debug was previously a paid-for feature, now available for free since v4.49

kunley4mo ago

dixie_land4mo ago

this is not true, `kubectl debug` attaches to the namespace of a container of your choosing (`--target` argument). You don't have to enable process namespace sharing at the pod level

kunley4mo ago

Last time I've checked, kubectl debug would not attach if namespace sharing wasn't enabled in the first place. Has it changed? What k8s version are you using?

PS. Even without checking again, it would be surprising if it changed. Even the official documentation is mentioning that this is needed

benterix4mo ago

Does podman contain or plan to implement something similar? Seems very useful.

kitd4mo ago

Not that I could find. There is always the option to use a sidecar container, eg:

https://matthewsanabria.dev/posts/no-shell-for-you-container...

https://iximiuz.com/en/series/mastering-container-debugging/

pella4mo ago

Only for "Docker Desktop 4.49 and later"

j / k navigate · click thread line to collapse