Hello, is it possible to have a domino server R5 and an R6 working at the same time? I’m talking about Notes client. On the web side I know that changing the http port works, but I’d like to know about the client side.
Thanks!
Subject: Just install the two servers as a partioned installation, and configure the ports according to the documentation on configuring partitioned servers.
Subject: I made it!
Well Bruce for what I’ve read the documentation says:
“When you set up a partitioned server, you must run the same version of Domino on each partition. However, if the server runs on UNIX®, there is an alternative means to run multiple instances of Domino on the server: on UNIX, you can run different versions of Domino on a single computer, each version with its own program directory. You can even run multiple instances of each version by installing it as a Domino partitioned server.”
So I can’t have R5 & R6 as a partitioned environment unless I’m running UNIX.
Well, it’s more simple than that, I hope I don’t find any further issues or problems.
I’ll show all my steps, not necessarily in this order or version.
1-Install a Domino R6
2-Install all R6 clients
3-Go to R6 Administrator and register a new server, with the same Organization and Domain.
4-Keep in mind to recover the id generated for this new server, because you’ll need it when you install the server.
5-Install the Domino R5 server as an additional server. Specify the same name/organization/domain as it was registered, and the path for the id created by R6.
6-The password for the new server would be the R6 administrator password.
7-Make R6 listen on Lan0 port and R5 listen on TCPIP
8-Just run both server 
9-And for the web just assign one of them a different port than 80
Hope it helps!
Subject: Interesting
and sorry about incorrectly advising you to use partitioning – guess I was thinking of how clustering doesn’t care about versions, and got them mixed up.
Subject: RE: I made it!
The only problem I see is that R5 cannot see R6, because one is listening on TCP and the other in LAN0.I don’t know how to make LAN1 available and what does it means !
Subject: RE: I made it!
LANn refers to a NetBIOS port. And obviously, two servers can’t communicate with each other if they’re not speaking the same network protocol. The only workaround I can see would be to have a third server on a different box run both protocols and gateway the communications between the other two – but if that were an option, I doubt that you’d be trying to set up two servers on the same box anyway.
Subject: RE: I made it!
well I messed up with all ports and so. Finally (and I don’t know how it could work) I have both servers with TCPIP and Lan0 enabled, same IP for them. The only difference I see is that one server listens on Lan0tcpip and the other one on Lan0ip, different names for the same thing.Now the two servers see each other with no problem at all (aparently).
Subject: Cool; you’ve achieved the seemingly impossible! Go for it!
Subject: Domino R5 & R6 working together on the same machine?
Hi,
I dont know if I understood you question correctly and I actually never tried to run two server on one machine simultanously.
But what you definitly can do for each domino server is to bind every of its “tasks” to a a specific IP adress (or port).
This way you could separate your two installations of notes servers that there wont be any conflicts on listening ports.
Look in the admin help for the topic “Configuring a partitioned server for one IP address and port mapping” how this is done through the notes.ini parameters “TCPIP_TcpIpAddress=0,IPAddress:1352” …
An other question is if you will be able to start the second server while the first one is still running :-)). Thats something you should try at first …
(try launching the nserver.exe manually as well)
Good luck and please post your results as this might be handy for others as well.
Bye
Hynek
Subject: RE: Domino R5 & R6 working together on the same machine?
well for now what i’ve got is a domino R5 and an R6 with all their clients for each version installed on an IBM thinkpad.
The two servers can be launched at the same time with no problem apparently. Then version 6 works fine (notes client and web) but version 5 only works in web. I’m not able to make it work on the client side, it doen’t connect to the server.
I’ve tried to enable lan1 but i don’t know much about it 
If I come to make it work I’ll put it here!