Troubleshooting

Connecting to a cluster via VPN doesn't work.

There are a few different issues that could arise when working with a VPN. Please see the dedicated page on Telepresence and VPNs to learn more on how to fix these.

Connecting to a cluster hosted in a VM on the workstation doesn't work

The cluster probably has access to the host's network and gets confused when it is mapped by Telepresence. Please check the cluster in hosted vm for more details.

Volume mounts are not working on macOS

It's necessary to have sshfs installed in order for volume mounts to work correctly during intercepts. Lately there's been some issues using brew install sshfs a macOS workstation because the required component osxfuse (now named macfuse) isn't open source and hence, no longer supported. As a workaround, you can now use gromgit/fuse/sshfs-mac instead. Follow these steps:

1. Remove old sshfs, macfuse, osxfuse using brew uninstall
2. brew install --cask macfuse
3. brew install gromgit/fuse/sshfs-mac
4. brew link --overwrite sshfs-mac

Now sshfs -V shows you the correct version, e.g.:

5. Next, try a mount (or an intercept that performs a mount). It will fail because you need to give permission to “Benjamin Fleischer” to execute a kernel extension (a pop-up appears that takes you to the system preferences).
6. Approve the needed permission
7. Reboot your computer.

Volume mounts are not working on Linux

It's necessary to have sshfs installed in order for volume mounts to work correctly during intercepts.

After you've installed sshfs, if mounts still aren't working:

1. Uncomment user_allow_other in /etc/fuse.conf
2. Add your user to the "fuse" group with: sudo usermod -a -G fuse <your username>
3. Restart your computer after uncommenting user_allow_other

No Sidecar Injected in GKE private clusters

An attempt to blackbird cluster intercept results in a timeout, and upon examination of the pods (kubectl get pods) it's discovered that the intercept command did not inject a sidecar into the workload's pods:

If this is occurring in a GKE cluster with private networking enabled, it is likely due to firewall rules blocking the Traffic Manager's webhook injector from the API server. To fix this, add a firewall rule allowing your cluster's master nodes to access TCP port 443 in your cluster's pods, or change the port number that Telepresence is using for the agent injector by providing the number of an allowed port using the Helm chart value agentInjector.webhook.port. Please refer to the telepresence install instructions or the GCP docs for information to resolve this.

Injected init-container doesn't function properly

The init-container is injected to insert iptables rules that redirects port numbers from the app container to the traffic-agent sidecar. This is necessary when the service's targetPort is numeric. It requires elevated privileges (NET_ADMIN capabilities), and the inserted rules may get overridden by iptables rules inserted by other vendors, such as Istio or Linkerd.

Injection of the init-container can often be avoided by using a targetPort name instead of a number, and ensure that the corresponding container's containerPort is also named. This example uses the name "http", but any valid name will do:

Telepresence's mutating webhook will refrain from injecting an init-container when the targetPort is a name. Instead, it will do the following during the injection of the traffic-agent:

1. Rename the designated container's port by prefixing it (i.e., containerPort: http becomes containerPort: tm-http).
2. Let the container port of our injected traffic-agent use the original name (i.e., containerPort: http).

Kubernetes takes care of the rest and will now associate the service's targetPort with our traffic-agent's containerPort.

Important note

If the service is "headless" (using ClusterIP: None), then using named ports won't help because the targetPort will not get remapped. A headless service will always require the init-container.

Error connecting to GKE or EKS cluster

GKE and EKS require a plugin that utilizes their resepective IAM providers. You will need to install the gke or eks plugins for Telepresence to connect to your cluster.

too many files open error when running blackbird cluster connect on Linux

If blackbird cluster connect on linux fails with a message in the logs too many files open, then check if fs.inotify.max_user_instances is set too low. Check the current settings with sysctl fs.notify.max_user_instances and increase it temporarily with sudo sysctl -w fs.inotify.max_user_instances=512. For more information about permanently increasing it see Kernel inotify watch limit reached.

Connected to cluster via VPN but IPs don't resolve

If blackbird cluster connect succeeds, but you find yourself unable to reach services on your cluster, a routing conflict may be to blame. This frequently happens when connecting to a VPN at the same time as telepresence, as often VPN clients may add routes that conflict with those added by telepresence. To debug this, pick an IP address in the cluster and get its route information. In this case, we'll get the route for 100.124.150.45, and discover that it's running through a tailscale device.

This will tell you which device the traffic is being routed through. As a rule, if the traffic is not being routed by the telepresence device, your VPN may need to be reconfigured, as its routing configuration is conflicting with telepresence. One way to determine if this is the case is to run blackbird cluster quit -s, check the route for an IP in the cluster (see commands above), run blackbird cluster connect, and re-run the commands to see if the output changes. If it doesn't change, that means telepresence is unable to override your VPN routes, and your VPN may need to be reconfigured. Talk to your network admins to configure it such that clients do not add routes that conflict with the pod and service CIDRs of the clusters. How this will be done will vary depending on the VPN provider. Future versions of telepresence will be smarter about informing you of such conflicts upon connection.