I was working on fail-over architecture for our application and came across this <duplicateDir> tag in application.xml which, I am quite sure that many of you advanced FMS users already know or some of you might be already using it in your FMS based applications to support Fail-over.
I designed an architecture for our application in this architecture I was trying to keep the same folder hierarchy on both server. So that if FMS (machine 1) stops working and users connects to same running instance from FMS (machine 2) they get the last updated data on FMS (machine 2) dumped through duplicate functionality from FMS1. There is a property in tag to attach application directory name to the path on other server or not i.e. by assigning value true you can add application directory name to the path or it will just copy the files at instance path. But when I was switching off the app directory name by assigning false it was just copying all sharedobject/streams at the root instead of at instance path. If I keep the app directory by assigning it true. It copies at correct path including instance path but attaching application directory path at beginning.
Anyway thinking that it’s some kind of bug or I might be doing something wrong. I posted a query regarding it on Flashcomguru mailing list and here comes the reply from FMS team member:
So what do we do now? I mean how do we achieve the duplicate directory functionality for fail-over in case we have planned for future? Or in case some of you were using it in past? So here is the reply from Adobe engineering team:
So good luck for all the FMS developers who were or are in process of implementing failover architecture and were planning to or already using this duplicate directory in their architecture.
Some other good way to implement failover is to follow architecture suggested by Rober A. Colvin
I am just curious to know that will NAS/SAN introduce any kind of latency? Compared to the files being stored on and delivered from same machine?
Please let me know if anyone has any idea about it.