From 02ac5b82413410ce34409c46f1030c64d77c4d6a Mon Sep 17 00:00:00 2001
From: "Lubomir I. Ivanov" <neolit123@gmail.com>
Date: Wed, 22 Aug 2018 23:30:33 +0300
Subject: [PATCH] troubleshooting-kubeadm: add guide for fixing stale CoreDNS
 pods (#9872)

---
 .../independent/troubleshooting-kubeadm.md    | 23 ++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/content/en/docs/setup/independent/troubleshooting-kubeadm.md b/content/en/docs/setup/independent/troubleshooting-kubeadm.md
index 4ba8688e6c..3019f7cac7 100644
--- a/content/en/docs/setup/independent/troubleshooting-kubeadm.md
+++ b/content/en/docs/setup/independent/troubleshooting-kubeadm.md
@@ -238,4 +238,25 @@ EOF
 )"
 
 ```
-{{% /capture %}}
\ No newline at end of file
+
+## `coredns` pods have `CrashLoopBackOff` or `Error` state
+
+If you have nodes that are running SELinux with an older version of Docker you might experience a scenario
+where the `coredns` pods are not starting. To solve that you can try one of the following options:
+
+- Upgrade to a [newer version of Docker](/docs/setup/independent/install-kubeadm/#installing-docker).
+- [Disable SELinux](https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/security-enhanced_linux/sect-security-enhanced_linux-enabling_and_disabling_selinux-disabling_selinux).
+- Modify the `coredns` deployment to set `allowPrivilegeEscalation` to `true`:
+
+```bash
+kubectl -n kube-system get deployment coredns -o yaml | \
+  sed 's/allowPrivilegeEscalation: false/allowPrivilegeEscalation: true/g' | \
+  kubectl apply -f -
+```
+
+{{< warning >}}
+**Warning**: Disabling SELinux or setting `allowPrivilegeEscalation` to `true` can compromise
+the security of your cluster.
+{{< /warning >}}
+
+{{% /capture %}}