Install Gremlin on OpenShift 4

Pre-requisites

Download authentication keys

Gremlin requires authentication during installation. You will need to download your Gremlin certificate key-pair in order to connect to your Gremlin team. With the key pair extracted to your local system, export the following variables into a local shell, supplying the appropriate values.

export GREMLIN_TEAM_ID=11111111-1111-1111-111111111111
export GREMLIN_CLUSTER_ID=my-cluster
export PATH_TO_CERTIFICATE=/path/to/unzipped/cert.pem
export PATH_TO_PRIVATE_KEY=/path/to/unzipped/key.pem

SELinux considerations

Gremlin's container targeting features require the Gremlin Agent to run with hostPID=true. OpenShift's container runtime CRI-O automatically runs hostPID containers with the spc_t SELinux process label. No custom SELinux profile installation is required.

Previous versions of Gremlin would allow hostPID=false and as a result required a custom SELinux module to grant the Gremlin agent access to system calls and file access. If you have installed a custom SELinux policy using Gremlin's 96-worker-gremlin-semodule MachineConfig, you should remove this MachineConfig and ensure the Gremlin Daemonset is installed with hostPID=true .

Helm installation

To install with Helm, log into the OpenShift cluster and run the following:

oc new-project gremlin
helm repo add gremlin https://helm.gremlin.com/
helm install gremlin gremlin/gremlin \
    --namespace gremlin \
    --set      gremlin.hostPID=true \
    --set      gremlin.hostNetwork=true \
    --set      gremlin.container.driver=crio-linux \
    --set      gremlin.podSecurity.securityContextConstraints.create=true \
    --set      gremlin.secret.managed=true \
    --set      gremlin.secret.teamID=$GREMLIN_TEAM_ID \
    --set      gremlin.secret.clusterID=$GREMLIN_CLUSTER_ID \
    --set-file gremlin.secret.certificate=$PATH_TO_CERTIFICATE \
    --set-file gremlin.secret.key=$PATH_TO_PRIVATE_KEY

Run attacks

You can now run experiments on your cluster, including Kubernetes experiments.

Troubleshooting

For common issues and solutions, see Troubleshooting Gremlin on OpenShift.