F5 versus DNS

Connectivity
Enthusiast

F5 versus DNS

Hi

Can anyone advise if an F5 load balancer should be used over a DNS, each configured with all Teradata COP's.  We have a 2650 Appliance running TD 13.10 with 15 nodes, 10 of which are Network connected.

The F5 administrator has advised that F5 just users round robin, whereas I thought a DNS was a bit smarter with how sessions are distributed.  The administrator also advised that high volumns of data should not go through the F5, and when we moved our backups to a DNS we saw quite an imporvement.  Should we also direct our Informatica load jobs to use the DNS instead of the F5 ?, and just keep the F5 for user sessions, as I believe the Customer still wants to use the F5, as other applications use it.

Any thoughts appreciated.

Cheers

Steve

3 REPLIES
Teradata Employee

Re: F5 versus DNS

The F5 load balancer is "smarter" than a typical DNS server, because the F5 keeps track of which database nodes are online vs offline, whereas a DNS server doesn't keep track of that information.

Teradata Client Engineering avoids making explicit recommendations about whether customers should, or should not, use an F5 load balancer. That is really the customer's decision, based on other factors that are relevant to the customer.

All the TTU client interface products (Teradata JDBC Driver, Teradata ODBC Driver, Teradata .NET Provider, Network CLI) support Laddered Concurrent Connect (LCC), which works well with either an F5 load balancer or a typical DNS server. With LCC, there is less need for the use of an F5 load balancer -- with LCC, you can now include Hot Standby Nodes (HSNs) in your DNS configuration.

Enthusiast

Re: F5 versus DNS

Thanks for the feedback, it was the LCC that I was referring to when I mentioned that DNS was a bit smarter, but thanks for advising the F5 also makes use of LCC

Are there any issues with large data volumns going through an F5 as opposed to the DNS, as we noticed a performance improvement when we moved our backups from using the F5 to the local host file with all COPS defined.

Cheers

Steve

Teradata Employee

Re: F5 versus DNS

>>> Are there any issues with large data volumns going through an F5 as opposed to the DNS

I have not heard that before. F5's marketing literature emphasizes their support for high volume network traffic. Perhaps the customer's F5 load balancer was undersized for the workload?