Add docker cluster pod errors due to too many open files (#7183)

Co-authored-by: Jiayi Wang <[email protected]>

docs/content/en/docs/troubleshooting/troubleshooting.md

@@ -101,6 +101,28 @@ Then verify you are using _cgroups v1_.
  Cgroup Version: 1
 ```
 
+### Pod errors due to `too many open files`
+
+The bootstrap or EKS Anywhere Docker cluster pods show error: `too many open files`.
+
+This may be caused by running out of [inotify](https://linux.die.net/man/7/inotify) resources. Resource limits are defined by `fs.inotify.max_user_watches` and `fs.inotify.max_user_instances` system variables. For example, in Ubuntu these default to 8192 and 128 respectively, which is not enough to create a cluster with many nodes.
+
+To increase these limits temporarily run the following commands on the host:
+
+```bash
+sudo sysctl fs.inotify.max_user_watches=524288
+sudo sysctl fs.inotify.max_user_instances=512
+```
+
+To make the changes persistent, edit the file `/etc/sysctl.conf` and add these lines:
+
+```bash
+fs.inotify.max_user_watches = 524288
+fs.inotify.max_user_instances = 512
+```
+
+Reference: https://kind.sigs.k8s.io/docs/user/known-issues/#pod-errors-due-to-too-many-open-files
+
 ### ECR access denied
 
 ```