text
stringlengths
0
59.1k
mountPath: "/cockroach/cockroach-data"
affinity:
podAntiAffinity:
preferredDuringSchedulingIgnoredDuringExecution:
- weight: 100
podAffinityTerm:
labelSelector:
matchExpressions:
- key: app
operator: In
values:
- cockroachdb
topologyKey: kubernetes.io/hostname
containers:
- name: cockroachdb
image: cockroachdb/cockroach:v1.1.0
imagePullPolicy: IfNotPresent
ports:
- containerPort: 26257
name: grpc
- containerPort: 8080
name: http
volumeMounts:
- name: datadir
mountPath: /cockroach/cockroach-data
command:
- "/bin/bash"
- "-ecx"
- |
# The use of qualified `hostname -f` is crucial:
# Other nodes aren't able to look up the unqualified hostname.
CRARGS=("start" "--logtostderr" "--insecure" "--host" "$(hostname -f)" "--http-host" "0.0.0.0")
# We only want to initialize a new cluster (by omitting the join flag)
# if we're sure that we're the first node (i.e. index 0) and that
# there aren't any other nodes running as part of the cluster that
# this is supposed to be a part of (which indicates that a cluster
# already exists and we should make sure not to create a new one).
# It's fine to run without --join on a restart if there aren't any
# other nodes.
if [ ! "$(hostname)" == "cockroachdb-0" ] || \
[ -e "/cockroach/cockroach-data/cluster_exists_marker" ]
then
# We don't join cockroachdb in order to avoid a node attempting
# to join itself, which currently doesn't work
# (https://github.com/cockroachdb/cockroach/issues/9625).
CRARGS+=("--join" "cockroachdb-public")
fi
exec /cockroach/cockroach ${CRARGS[*]}
# No pre-stop hook is required, a SIGTERM plus some time is all that's
# needed for graceful shutdown of a node.
terminationGracePeriodSeconds: 60
volumes:
- name: datadir
persistentVolumeClaim:
claimName: datadir
volumeClaimTemplates:
- metadata:
name: datadir
spec:
accessModes:
- "ReadWriteOnce"
resources:
requests:
storage: 1Gi
<|endoftext|>
# source: k8s_examples/_archived/cockroachdb/README.md type: docs
# CockroachDB on Kubernetes as a StatefulSet
This example deploys [CockroachDB](https://cockroachlabs.com) on Kubernetes as
a StatefulSet. CockroachDB is a distributed, scalable NewSQL database. Please see
[the homepage](https://cockroachlabs.com) and the
[documentation](https://www.cockroachlabs.com/docs/) for details.
## Limitations
### StatefulSet limitations
Standard StatefulSet limitations apply: There is currently no possibility to use
node-local storage (outside of single-node tests), and so there is likely
a performance hit associated with running CockroachDB on some external storage.
Note that CockroachDB already does replication and thus it is unnecessary to
deploy it onto persistent volumes which already replicate internally.
For this reason, high-performance use cases on a private Kubernetes cluster
may want to consider a DaemonSet deployment until Stateful Sets support node-local
storage (see #7562).
### Recovery after persistent storage failure
A persistent storage failure (e.g. losing the hard drive) is gracefully handled
by CockroachDB as long as enough replicas survive (two out of three by
default). Due to the bootstrapping in this deployment, a storage failure of the
first node is special in that the administrator must manually prepopulate the
"new" storage medium by running an instance of CockroachDB with the `--join`
parameter. If this is not done, the first node will bootstrap a new cluster,
which will lead to a lot of trouble.
### Dynamic volume provisioning
The deployment is written for a use case in which dynamic volume provisioning is