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```Diagnostics:
 
data-feed-control (aws:elasticache:Cluster)
error: unmarshaling urn:pulumi:development::platform-data-feed::aws:elasticache/cluster:Cluster::data-feed-control's instance state: could not read field snapshot_arns: '' expected type 'string', got unconvertible type '[]interface {}', value: '[]'
 
Resources:
    132 unchanged
 
Duration: 18s```

I really do not get which file in the project is provoking that

```
  return new aws.elasticache.Cluster('data-feed-control', {
    clusterId: 'data-feed-control',
    engine: 'redis',
    engineVersion: '2.8.24',
    nodeType: 'cache.t3.micro',
    numCacheNodes: 1,
    parameterGroupName: 'default.redis2.8',
    subnetGroupName: feedControlSubnetGroup.id,
    securityGroupIds: [defaultSecurityGroup.id]
  })
}```

but I do not get where  snapshot_arns comes from

<https://www.pulumi.com/docs/reference/pkg/aws/elasticache/cluster/#snapshotwindow_nodejs>

Screenshot 2021-05-13 at 11.51.08.png

got the feeling that is this one :slightly_smiling_face:

but it is not mandatory.... why does is it fail for that?

``` aws:elasticache:Cluster (data-feed-control):
    error: unmarshaling urn:pulumi:development::platform-data-feed::aws:elasticache/cluster:Cluster::data-feed-control's instance state: could not read field snapshot_arns: '' expected type 'string', got unconvertible type '[]interface {}', value: '[]'```

```  return new aws.elasticache.Cluster('data-feed-control', {
    clusterId: 'data-feed-control',
    engine: 'redis',
    engineVersion: '6.x',
    nodeType: 'cache.t3.micro',
    numCacheNodes: 1,
    parameterGroupName: 'default.redis6.x',
    securityGroupIds: [defaultSecurityGroup.id],
    subnetGroupName: feedControlSubnetGroup.id,
    snapshotArns: 'arn:aws:s3:::backup-jx-dev-20210209181727146100000009/redis-snapshots/'
  })```

```import * as pulumi from "@pulumi/pulumi";
import * as aws from "@pulumi/aws";

const example = new aws.elasticache.Cluster("example", {
    engine: "redis",
    engineVersion: "3.2.10",
    nodeType: "cache.m4.large",
    numCacheNodes: 1,
    parameterGroupName: "default.redis3.2",
    port: 6379,
});```

I think you’re running into <https://github.com/pulumi/pulumi/issues/6943> where the underlying type has changed and so the state written with the previous version of the provider no longer works

Oh, nevermind. I see you found the issue :slightly_smiling_face:

Per <https://github.com/pulumi/pulumi-aws/issues/1458> you can workaround this by modifying the state.