I m getting a failure converting to a multi AZ RDS cluster `

Question

I m getting a failure converting to a multi AZ RDS cluster ``` + aws rds Cluster postgres replace diff ~availabilityZones dbClusterInstanceClass ``` Error ``` error 1 error occurred creating RDS Cluster DBClusterAlreadyExistsFault DB Cluster already exists status code 400 request id ``` I m still testing the deployment so I m going to bring the whole thing down and go from there just wondering if this is expected `deletionProtection` is disabled

billowy-army-68599 · Answer

did you set an explicit name for the db

salmon-musician-36333 · Answer

`clusterIdentifier` If so yes

billowy-army-68599 · Answer

set delete before replace before changing the properties

salmon-musician-36333 · Answer

Right on thanks a bunch slightly smiling face

salmon-musician-36333 · Answer

In general is the recommended approach to not set explicit names except where absolutely necessary in order to let Pulumi bring stuff up while the previous incarnation still exists

billowy-army-68599 · Answer

yes ideally

salmon-musician-36333 · Answer

I ve had a few cases where it was to resolve a circular dependency e g having to specify an ARN for something else before the resource was up although that s usually policies and I could attach the policy after the dependencies are created Otherwise it s for interacting with things outside of Pulumi which expect the resources to have certain names which is a harder problem to fix but I could potentially audit what those are and dump the rest

salmon-musician-36333 · Answer

Tbh for the RDS situation I ll eventually look into whether I can have Pulumi migrate data from one to another while they are both up if there are hooks to do such a thing

salmon-musician-36333 · Answer

On a related note I m running into this now with `finalSnapshotIdentifier` I would generate a tag based on the date but then it s going to end up modifying replacing the cluster every run Is there a way to ask Pulumi for a unique hopefully prefixed identifier that will be persisted in state

salmon-musician-36333 · Answer

This is what I m referring to ``` error deleting urn pulumi aws rds cluster Cluster postgres 1 error occurred deleting RDS Cluster DBClusterSnapshotAlreadyExistsFault Cannot create the cluster snapshot because one with the identifier already exists ```

billowy-army-68599 · Answer

yeah use `pulumi random` to generate a random id slightly smiling face

salmon-musician-36333 · Answer

< billowy army 68599> Nice I ve set that up with `finalSnapshotIdentifier` like so ``` finalSnapshotIdentifier postgresRetainFinalSnapshot postgresFinalSnapshotNameRandom hex undefined ``` Hopefully that looks reasonable I feel like `keepers` might be relevant but it says to look at the `random Provider` docs which don t explain too much wink

salmon-musician-36333 · Answer

Now I m getting a dependency issue again bringing down a security group but this time the explicit `dependsOn` is there which is troubling ``` error deleting urn pulumi aws rds subnetGroup SubnetGroup 1 error occurred deleting RDS Subnet Group InvalidDBSubnetGroupStateFault Cannot delete the subnet group because at least one database cluster is still using it ```

salmon-musician-36333 · Answer

But the dependency is there for the cluster ``` dependsOn postgresSg deleteBeforeReplace true ``` Know what might be up

gentle-daybreak-46874 · Answer

Think that s the opposite The subnet group depends on the cluster too at least you cannot delete it until the cluster is gone

salmon-musician-36333 · Answer

< gentle daybreak 46874> If you can t delete the SG until the cluster is gone then the cluster depends on the SG `dependsOn x y ` means the resource needs to come up after `x` and `y` and be brought down before `x` and `y`

salmon-musician-36333 · Answer

< billowy army 68599> Does the usage of `pulumi random` above seem legit

salmon-musician-36333 · Answer

I m thinking it will be treated like any other dependent resource and will only come down when the cluster goes down which is basically what a final snapshot should have

salmon-musician-36333 · Answer

But maybe it needs to be cross linked with `keepers x somethingFromCluster apply x = gt `

salmon-musician-36333 · Answer

Since it s higher in the dependency hierarchy that may work fine when I m bringing the whole deployment down but not convinced it s enough without `keepers` for a recreate

salmon-musician-36333 · Answer

On the other hand this looks a little bit fishy to me slightly smiling face ```const postgresSgName = `$ deployTag postgres sg` const postgresClusterIdentifier = `$ deployTag postgres` let postgresFinalSnapshotNameRandomKeepers Record lt string string gt = const postgresFinalSnapshotNameRandom = new random RandomId postgres final snapshot random prefix `$ deployTag postgres final snapshot ` byteLength 4 keepers postgresFinalSnapshotNameRandomKeepers const postgresCluster = new aws rds Cluster postgresCluster id apply id = gt postgresFinalSnapshotNameRandomKeepers clusterId = id ```