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Citrix ICA file TcpBrowserAddress parameters

We have some third-party Citrix servers we connect to via an ICA file that includes three TcpBrowserAddress fields consisting of two different server names and one IP address.

The app in question is being moved to some new Citrix servers in a new farm.  The citrix servers are part of a DNS zone that the clients don't have access to, instead a few key A records are in the DNS zone of the clients.  As a result of this, we're contemplating just redirecting the relevant mirrored A records in the client's zone to point to the new servers instead rather than deploying new ICA files (the app name is unchanged).

One of the TcpBrowserAddress entries though is by IP and cannot be migrated that way.

My question then is to how the Citrix Client (v9.230) handles multiple TcpBrowserAddress entries in an ICA file.  Does it only use entry 2 if entry 1 doesn't answer; or is it random; or does it talk to them all at once?

I'm a little concerned that it uses them all at once and accepts the first reply (which would cause problems if the server specified by IP cannot be decomissioned immediately).  My reason for thinking that all three may be talked to at once is the following article:
That talks about the PN.ini file.  The only info I have on ICA files suggests their config matches that of APPSRV.INI (with no mention of PN.ini).

Anyone know the definitive answer?  An online reference would be appreciated.  Thanks!
CitrixWindows XP

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8/22/2022 - Mon
Ayman Bakr

This link will help you:


Bottom-line, the client will connect using any of these mentioned servers to determine the ICA master browser; then that one will provide the server (least loaded) which has the application (and it doesn't have to be any of those mentioned servers).

I had seen that page before but it's not clear as to when the alternate addresses are used.  The link that the person answering there quotes make no reference to the behaviour of multiple entries either - it actually recommends using just one.
Ayman Bakr

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Ah that looks pretty definitive, thanks  :)
It's not talking about ICA files specifically, but I suspect this behaviour must be universal for that parameter in whichever file, since it's also described as the case for in the PN.ini file too.

I've done some experimenting and with an ICA file with three address entries - two by hostname and one by IP, it's always connecting to the one specified by IP initially - just the overhead of name resolution must be causing them to lag behind that one in responding!
Your help has saved me hundreds of hours of internet surfing.

Just spotted your link says:

" If an ICA file is being used, the master browser request is made to the TCPBrowser entries. "