roachtest: cluster_creation failed

roachtest.cluster_creation [failed](https://teamcity.cockroachdb.com/buildConfiguration/Cockroach_Nightlies_RoachtestNightlyAwsBazel/20645303?buildTab=log) with [artifacts](https://teamcity.cockroachdb.com/buildConfiguration/Cockroach_Nightlies_RoachtestNightlyAwsBazel/20645303?buildTab=artifacts#/kv95/enc=false/nodes=4) on release-25.2 @ [76e2fe3218b3dab0b876b61c3eb68ed3fe944601](https://github.com/cockroachdb/cockroach/commits/76e2fe3218b3dab0b876b61c3eb68ed3fe944601):

```
test kv95/enc=false/nodes=4 failed: (test_runner.go:840).func4: in provider: aws: failed to run: aws ec2 run-instances --associate-public-ip-address --count 1 --instance-type m6id.2xlarge --image-id ami-0e83be366243f524a --key-name teamcity-runner-Cn8srGSnjCMxe_JfFNpvHA2s-xQ= --region us-east-2 --security-group-ids sg-04d72b57e29d671f1 --subnet-id subnet-0258dc9d1b6473d84 --tag-specifications ResourceType=instance,Tags=[{Key=usage,Value=roachtest},{Key=roachtest-branch,Value=release-25-2},{Key=lifetime,Value=12h0m0s},{Key=arch,Value=amd64},{Key=created,Value=2025-10-24T06:27:56Z},{Key=Name,Value=teamcity-20645303-1761284522-46-n5cpu8-0004},{Key=Cluster,Value=teamcity-20645303-1761284522-46-n5cpu8},{Key=spot,Value=true},{Key=roachprod,Value=true},{Key=cluster,Value=teamcity-20645303-1761284522-46-n5cpu8}] ResourceType=volume,Tags=[{Key=usage,Value=roachtest},{Key=roachtest-branch,Value=release-25-2},{Key=lifetime,Value=12h0m0s},{Key=arch,Value=amd64},{Key=created,Value=2025-10-24T06:27:56Z},{Key=Name,Value=teamcity-20645303-1761284522-46-n5cpu8-0004},{Key=Cluster,Value=teamcity-20645303-1761284522-46-n5cpu8},{Key=spot,Value=true},{Key=roachprod,Value=true},{Key=cluster,Value=teamcity-20645303-1761284522-46-n5cpu8}] --user-data file:///tmp/aws-startup-script576652057 --iam-instance-profile Name=roachprod-testing --block-device-mapping file:///tmp/aws-block-device-mapping1088531666 --instance-market-options MarketType=spot,SpotOptions={SpotInstanceType=one-time,InstanceInterruptionBehavior=terminate} --output json: stderr:
An error occurred (InsufficientInstanceCapacity) when calling the RunInstances operation (reached max retries: 2): We currently do not have sufficient m6id.2xlarge capacity in the Availability Zone you requested (us-east-2a). Our system will be working on provisioning additional capacity. You can currently get m6id.2xlarge capacity by not specifying an Availability Zone in your request or choosing us-east-2b, us-east-2c.: exit status 254 [owner=test-eng]
```

Parameters:
- cloud=aws
- coverageBuild=false
- cpu=8
- runtimeAssertionsBuild=false
- ssd=0
Help

See: [roachtest README](https://github.com/cockroachdb/cockroach/blob/master/pkg/cmd/roachtest/README.md)

See: [How To Investigate \(internal\)](https://cockroachlabs.atlassian.net/l/c/SSSBr8c7)

/cc @cockroachdb/test-eng

[This test on roachdash](https://roachdash.crdb.dev/?filter=status:open%20t:.*cluster_creation.*&sort=title+created&display=lastcommented+project) | [Improve this report!](https://github.com/cockroachdb/cockroach/tree/master/pkg/cmd/bazci/githubpost/issues)

Jira issue: CRDB-55763

Start with the roachtest README and the linked TeamCity log for cluster_creation on release-25.2. Trace the AWS provider path that invokes ec2 run-instances and compare its handling of the reported InsufficientInstanceCapacity error. Done means the cluster_creation test completes successfully in the reported setup, with the capacity failure addressed or its handling clearly established.

Written by the indexing model from the issue text.