Livenessprobe, Readinessprobe

Livenessprobe:

if the disk is under heavy pressure the default 5s seem a little bit optimistic to read the rs.info. What is the max value that makes sense resp. are there other options avail ?

Readinessprobe:

Tries to list all the databases. If you have like xxx’xxx databases, this call doesn’t make sense at all. Is there a way to change that resp. can a different readinessprobe applied ?

=> in both cases if there are too many failures the pods are getting shutdown. Clients can accept a long response time or even a timeout. But if they have to wait until the replicaset has done the restarted - it is just not a sensible way of doing the probes (imho) - or at least there should be other options.

2 Likes

Hello @jamoser ,

we had similar thread here: Liveness and Readiness probe failed

Right now it is not possible to tune the probes through the operator.

Tries to list all the databases. If you have like xxx’xxx databases, this call doesn’t make sense at all. Is there a way to change that resp. can a different readinessprobe applied ?

This seems to be a suboptimal solution, I agree.

1 Like

Is this because of Percona Operator or MongoDB Operator ?

1 Like

I don’t get the question. What about MongoDB Operator?

1 Like

To change the liveness and readiness probe. In kubernetes usually you could create your own probes. So is it not possible because the Percona Operator does not provide an interface or is it the MongoDB Operator ?

1 Like

I’m still confused about

Percona Operator does not provide an interface or is it the MongoDB Operator

Percona k8s Operator for MongoDB does not have anything in common with MongoDB Operator. These are two different code bases.

Changing liveness and readiness probes configuration is not possible currently through Percona Operator. It is not implemented.
We have a task to tune the timeouts here: [K8SPSMDB-527] Allow tuning timeout parameters for probes - Percona JIRA

Also as promised I will discuss with the team the suboptimal solution of a probe listing databases.

2 Likes

in fact liveness probe is tuneable percona-server-mongodb-operator/cr.yaml at main · percona/percona-server-mongodb-operator · GitHub
readiness probes is simple - it just checks if mongod port is accessible

1 Like

For mongos our readiness probe runs listDatabases @Mykola .

2 Likes