F5 Global Traffic Manager

Hi folks,

 

 

I have been asked to look into, and prepare a paper on the implementation of a global load balancing solution for our two data centres, one based in Manchester, UK & the other based in Guildford, UK. At present, we manually configure failover by updating DNS entries, which can take upto 24 hours to propagate to all servers on the Internet.

 

 

When doing research, I have come across the F5 Global Traffic Manager (GTM) product, which at a high level appears to do exactly what we want it to do.

 

 

Unfortunately, the information I can find about the product is limited, it is either really vague, or really technical.

 

 

My understanding of the solution we require so far is:

 

 

- We will have (atleast) one unit in each site

 

 

- These act as the authoratative servers for our domain (3Dns)

 

 

- These communicate internally using iQuery (I assume this is similar to HSRP/VRRP in networking) and should a failure occur in either site, the failed servers are removed from the "virtual site" (there can be upto 10 seconds of downtime for some users due to caching)

 

 

 

Unfortunately i'm still unable to get my head around the DNS aspect, and also have the following questions:

 

 

- is replication between devices stateful, i.e if there is a failover during active connections, will these continue to be served or will they time-out?

 

 

- what happens should the internal heartbeat be lost between devices but the upstream Internet connections continue to function fine, can the device communicate using a VPN-style public connection?

 

 

Any info that can be given would be greatly received.

 

 

Best regards,

 

 

Peter