This adds a small C binary for fighting zombies. It is mounted under
`/dev/init` and is prepended to the args specified by the user. You
enable it via a daemon flag, `dockerd --init`, as it is disable by
default for backwards compat.
You can also override the daemon option or specify this on a per
container basis with `docker run --init=true|false`.
You can test this by running a process like this as the pid 1 in a
container and see the extra zombie that appears in the container as it
is running.
```c
int main(int argc, char ** argv) {
pid_t pid = fork();
if (pid == 0) {
pid = fork();
if (pid == 0) {
exit(0);
}
sleep(3);
exit(0);
}
printf("got pid %d and exited\n", pid);
sleep(20);
}
```
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Allows the user to use `pretty` as the format string.
This enables users to put custom format options into their CLI config
just like is supported for `docker ps` and `docker images`
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Because we standardize on using a non-privileged
prompt (`$`) instead of `#`, replacing the
examples to use `sudo` instead to indicate
this has to be run as root.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The "format" example got lost during the
rewrite of the documentation for Cobra. This
restores the missing example.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The indexing of steps in the output of `docker build` starts with `Step 1`.
However, there are several places in the docs that start with `Step 0`.
This fix addresses the issue and changes `Step 0` to `Step 1` (and subsequent steps).
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
The restriction is no longer necessary given changes at the runc layer
related to mount options of the rootfs. Also cleaned up the docs on
restrictions left for userns enabled mode. Re-enabled tests related to
--read-only when testing a userns-enabled daemon in integration-cli.
Docker-DCO-1.1-Signed-off-by: Phil Estes <estesp@linux.vnet.ibm.com> (github: estesp)
As is raised in 26312, in `docker network ls`, the help output was
mistaken to `volume names`:
```
-q, --quiet Only display volume names
```
This fix changes the help output to:
```
-q, --quiet Only display network IDs
```
This fix also updates the documentation in:
`docs/reference/commandline/network_ls.md`
This fix fixes 26312.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
When xfs filesystem is being used on top of thin pool, xfs can get ENOSPC
errors from thin pool when thin pool is full. As of now xfs retries the
IO and keeps on retrying and does not give up. This can result in container
application being stuck for a very long time. In fact I have seen instances
of unkillable processes. So that means once thin pool is full and process
gets stuck, container can't be stopped/killed either and only option left
seems to be power recycle of the box.
In another instance, writer did not block but failed after a while. But
when I tried to exit/stop the container, unmounting xfs hanged and only
thing I could do was power cycle the machine.
Now upstream kernel has committed patches where it allows user space to
customize user space behavior in case of errors. One of the knobs is
max_retries, which specifies how many times an IO should be retried
when ENOSPC is encountered.
This patch sets provides a tunable knob (dm.xfs_nospace_max_retries) so
that user can specify value for max_retries and tune xfs behavior. If
one sets this value to 0, xfs will not retry IO when ENOSPC error is
encountered. It will instead give up and shutdown filesystem.
This knob can be useful if one is running into unkillable
processes/containers issue on top of xfs.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
