# Troubleshooting instance transfer
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**Important**  
This content is for IT administrators who have experience investigating network and telephony issues. You must be familiar with accessing data in Amazon Connect contact records.

## Locate instance transfer information
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Amazon Connect provides information in the contact record for each connected call. If a call transfers between two different instances, you can view this information in the contact record.

The following example shows the `connect:CrossInstanceInfo` segment attributes:

```
"Contact": {
    ...
    "SegmentAttributes": {
        "connect:CrossInstanceInfo": {
            "ValueMap": {
                "RelatedInitialContactARN": {
                    "ValueArn": "arn:aws:connect:us-west-2:111111111111:instance/fead664d-f209-4779-840e-e9e3d3ad8093/contact/609a5b3a-e28a-41a5-a86d-a0cff9529eeb"
                },
                "RelatedContactARN": {
                    "ValueArn": "arn:aws:connect:us-west-2:111111111111:instance/fead664d-f209-4779-840e-e9e3d3ad8093/contact/609a5b3a-e28a-41a5-a86d-a0cff9529eeb"
                }
            }
        },
        "connect:ConnectionType": {
            "ValueString": "CONNECT"
        }
    }
    ...
}
```

For parameter descriptions, see [Segment attributes](connect-attrib-list.md#attribs-segment-attributes). You must set up instance-to-instance calls and follow the architectural guidance.

## Understand instance transfer scenarios
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Calls can move between instances multiple times, creating complicated call flows. To simplify validation, there are two scenarios that can be repeat throughout this process.

### Scenario 1: Outbound initiated call
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This scenario occurs when you make an outbound call to another on-network Amazon Connect number without any existing call in the system.

 **How it works:** 
+ The system adds the inbound contact ARN on the second instance to the ` RelatedInitialContactARN` and `RelatedContactARN` segment attributes on the first contact.
+ For the inbound call on the second instance, both ` RelatedInitialContactARN` and `RelatedContactARN` are set to the original outbound contact ARN.

**Note**  
This scenario only occurs on the first original outbound call.

### Scenario 2: Transfer an existing inbound call
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This scenario occurs when you transfer an existing inbound contact to a phone number in any of your Amazon Connect instances. The instance (referred to as the 'second instance' below) can be the same instance that the call is transferring from.

 **On the first instance there are two contacts:** 

1. The inbound contact:
   + `InitialContactID` and `PreviousContactID` are blank, as this is the initial contact.
   + `NextContactId` references the transfer contact below.
   + `connect:CrossInstanceInfo` is not populated.

1. The transfer contact:
   + `InitialContactID` and `PreviousContactID` reference the inbound contact above.
   + `connect:CrossInstanceInfo` is populated with 2 nested attributes, ` RelatedInitialContactARN` and ` RelatedContactARN`. Both contain the contact ARN that was generated on the second instance, detailed below.

 **On the second instance, there is one contact:** 

1. The inbound contact:
   + `InitialContactID`, `PreviousContactID`, and ` NextContactID` are all blank.
   + `connect:CrossInstanceInfo` is populated with 2 nested attributes, ` RelatedInitialContactARN` and ` RelatedContactARN`.
   + `RelatedInitialContactARN` is populated with the inbound contact ARN in the first instance. (In case of multiple transfer, this value will be the ARN of the inbound contact that initiated the latest transfer - Want to make sure if this is clear, otherwise, we can remove this)
   + `RelatedContactARN` is populated with the transfer contact ARN in the first instance

**Important**  
If multiple transfers occur within the original instance before the instance to instance transfer, the system only references the external transfer and the original inbound call. Internal transfers are not referenced.

## Analyze your call flow
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You can use the preceding information to debug how your call flowed through your environment.

**To trace a call flow**

1. Start with the inbound call to the instance.

1. Look up the inbound call in the contact record.

1. If the call was transferred, the record provides both the original inbound call from the previous instance and the outbound call from that instance to the current one.

1. Repeat this pattern to track back through all instance transfer between different instances.