Concurrent UPSERT changes to a SRV record

Question

Say there exists an SRV record that may be modified by either adding another value or removing a value.

Value being a: [priority] [weight] [port] [server host name].

These modifications could happen concurrently, and could result in race conditions.

1. Get SRV
2. send an UPSERT change that adds a new value

or...
1. Get SRV
2. send an UPSERT change that removes a value in the SRV

What mechanism could be in place to prevent race conditions? Is there a way to put the GET and UPSERT steps in the same transaction?

Answer

Hello, 
Thank you for reaching out to AWS re-post.

I understand that you need some queries regarding concurrent UPSERT changes to a SRV record that may lead to race around condition.

You can split UPSERT to DELETE & CREATE in one API call. The first one to DELETE the value from previous GET and then CREATE the new value. Route53 would check if the value in DELETE matches what's in the DB.
If you are using any script, a random jitter or sleep between two tasks might help get rid of the race around condition.
For better understanding of the issue, I would request you to contact out AWS route 53 support team via support centre. So that you can better explain the use case with your resources working upon.
This query needs some replication to be done in order to find a workaround.

Answer

Hello,

Thank you for contacting AWS Re:post.

I understand you have some clarifications regarding concurrent UPSERT changes to a SRV record.

Going through the use case, I would suggest you to contact out AWS route 53 support team via support center as they would be able to replicate the use case and get back to you with all the details.

Concurrent UPSERT changes to a SRV record

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