cname record for aurora rds update time - amazon-rds

I am thinking of moving from mysql --> aurora and have a question in regards to cname
In route 53 I have a dns CNAME for my database that points to the RDS endpoint; can I just update the cname records after I promote aurora to production to point to the aurora instance. Will there be any delay in my application getting this update? EC2 would be connecting to the database in the same region.

If you want to continue to use CNAMES, go to your DNS server and make note of the TTL value for this entry. Change the entry to the shortest TTL value.
Wait for the amount of time specified by the old TTL. Upgrade from RDS MySQL to Aurora. Change the DNS entry to point to the new server. Change the TTL back to its previous value.
By following the above steps you will minimize the DNS resolution switch over time.

Related

RODC to Main DC for DNS query, but in differnet locations; how to get queries in local region>?

We use CXOne CaaS phone system which then assigns an RTC server to our logged in agents based on where the DNS is being queried from.
Our primary DC sits in France, and we have a local RODC which goes back to the primary DC to get the DNS queries, but this is forcing the Caas Solution to pick up france servers for routing.
Is there no way to make it to do Australian queries, without manually adding in DNS records?
Tried:
host file manually changing each DNS is not ideal, as I.P could change from provider

Application using fasthttp(go) cannot resolve domain ip with fixed domain after expiring dns TTL

My team uses eks + istio and here is the tricky situation.
A golang application container is deployed with istio-proxy container in a same eks pod. This application uses fasthttp to communicate another external service outside of eks. This external service can be resolved as a specific domain name enlisted on aws route53. After I changed A record of this domain with 300 seconds of TTL and wait for 300 seconds of TTL expiration, I was able to resolve changed A record with nslookup command from the application container but the application process tried to connect old A record with same domain. After re-deploy this application, this application can resolve new A record.
Here is the question. Is it possible HTTP connection pool or HTTP connection caches remember old A record after dns TTL expiration no matter what its container already resolving new A record?

Azure DNS Time response

We have a application hosted on top of compute instance Azure Cloud. The DNS Query seems to be quite Slow. Can we check somehow why the response is so slow and whether there is some caching at the OS Level.
The reason behind the Azure DNS slow response maybe due to below:
When you create new DNS zones and DNS records in the Azure DNS name servers they will appear quickly in few seconds.
When you are trying to modify existing DNS records this may take a little longer.
It may take up to 60 seconds to reflect in Azure DNS name servers.
As you mentioned, 'DNS caching by DNS clients and DNS recursive resolvers outside of Azure DNS also can affect timing.'
Use Time-To-Live (TTL) property to manage cache duration for the record set.
Time-To-Live (TTL) represents how long each record is cached by clients before being re-queried.
TTL value ranges between 1 and 2,147,483,647 seconds.
For more in detail, please refer the below links:
https://learn.microsoft.com/en-us/azure/dns/dns-faq#how-long-does-it-take-for-dns-changes-to-take-effect-
https://learn.microsoft.com/en-us/azure/dns/dns-zones-records#time-to-live

Elixir Ecto - DNS Resolution

We have a Phoenix App that is connecting to an AWS Aurora RDS instance for the database. However, we are using the DNS string (e.g. company.cluster-sdfssfd.us-east-1.rds.amazonaws.com) which is dynamic. Last night we noticed that the underlying ips were rotated by AWS, however, our app did not pick up on these changes and was trying to write to the old dns mapped host which was now a read-only replica. How can we get Phoenix/Ecto to automatically refresh the DNS?

How to setup a dns for an ip address

I setup up a HTTP server in home that is connected to the internet. I registered .COM a domain. Now I want to use this domain to connect to my server. but when i try to set my IP address as DNS I see this error :
Unable to update nameservers: Nameserver [MYIPADDRESS] doesn't exist at the registry
Nameservers indicates what server owns the DNS records for the zone, you need to create A records, not update the Nameserver. If you are on GoDaddy, switch to the "DNS Zone File" tab and then create an A record instead of trying to change the nameserver records.
You may want to check your TTL (Time To Live) value for the A-record. If the TTL is set to a higher time quanta, the changes will take a lot longer to propagate as the old IP address would still be cached.
Changing NS records would not be the ideal solution for what you are looking to accomplish as you are most likely not shunting traffic from one authoritative DNS server to another to answer queries for your zone.

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