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Citrix I/O Error

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Disarray0019

Technical User
Feb 9, 2003
18
US
I have a strange problem, where ICA clients are unable to launch a published application. They can launch the server desktop and launch applications from within, but not the application in a seamless window. When launching the application, I receive the following error:

Cannot conect to Citrix server.
I/O Error.

The thing that is so strange, is that this happens randomly. By randomly, I mean that it was working, then I started configuring my server further (setup routing and ISS) and it quit working. Before the problem occurred, I backed up my server, and then made the configuration changes. Once the errors started to occur, I restored from my backup, and it started to work again. I figured it was either the routing changes, or the fact that I made changes to IIS. So, I first made the changes to IIS again, and I started to get the I/O errors again. I restored again, and made my routing changes, without touching IIS. This time, right after the changes, I wasn't getting the errors and I could launch applications. Then about an hour later, the errors started again. Now, when I restore my backup, there is no change, and I keep getting the I/O errors. This leads me to believe that it was just a coincidence, and it wasn't the chages to routing or IIS, but something else causing the errors. Other than routing and IIS changes, I've done nothing to my server. Even though I don't see how it could be my published app settings since it worked before, I've tried every setting possible.

This is only a two system test LAN with a w2k server runing Citrix XP 1.0, and a WinXP workstation with the most current ICA client.

I've looked for people with the same problem, but have found nothing. Has anyone here had these I/O errors before? Thanks in advance for any help / suggestions.
 
Something I never tested before, was to try to launch seamless apps on the citrix server itself. I decided to try this, and they do launch from within the server. Does this help anyone to help me? Seems like some sort of a networking issue, but I don't know where to look, since it just decided to stop working all of the sudden. My server has 3 NIC's. One connecting to the internet 63.#.#.#, one to a solaris 9 machine 10.0.2.1 (which is currently powered off), and one to windows XP 10.0.1.1. Thanks again for any help.
 
Well try going into the Citrix Connection Configuration and setting it to use the adapter that is the network that you want.

Good Luck,
Steve Thank You,
Steve
 
Thank you for the suggestion. It was set to use all adapters, but I tried setting it to just use the NIC connecting to my XP machine with no luck. Thanks again.
 
While troubleshooting my problem, I noticed that in my RAS settings (I configured my server as an internet sharing server with NAT), when I click on the "General" section of the "IP Routing" sub-catagory of my server, it shows my Internal interface as Non-operational. There are 5 interfaces in that section, one for each NIC, one for the Loopback, and one for the Internal interface. The ip shows up as "Not available", the Administrative Staus shows as "Unknown", and as I said before, the "Operational Status" is Non-operational. I've seen this interface show up as operational before, but never paid attentention till now, does anyone know if this could be causing my problem? I've tried disabling RRAS, and re-enabling it, but with no change. I know this may be getting into an OS / networking question, but since it may be related to my publish apps question, I hope it's ok here. As before, thanks for any help.
 
It seemed like everyone that was having the same problem as me, was able to get their applications to run with NFuse, so I decided to try that. I can log in (NFuse 1.6), and I get my application icons. When I double click the icon, the connecting dialog box pops up, but it fails to connect. I am receiving the following error:

The Citrix Server is not available, please try again later.

Anyone have any suggestions?
 
Looks like I'm alone on this one. I'm not 100% on which change fixed my problem, but the things I did to get my apps working via NFuse are listed below (I'm sure some of my changes neither helped nor hurt my situation, but soon I'll reverse my changes one by one till it quits working, in case there are any other beginners out there like me, that may be having the same problems).

I think one thing that would help me out and possibly others as well, is to know what changes require a reboot. I've read some articles that say a server reboot is required for one task, and other articles that say you don't need to reboot (ex. altaddr change). Maybe this exists, and I just haven't seen it yet.

First I changed the citrix xml port to 8080 with ctxxmlss /R8080. After that, I changed the port that my IIS server runs on, to 8080 as well. I made sure to change every interface instance to port 8080, not just my external device. I then added alternate addresses for each internal NIC behind NAT with the altaddr command (altaddr /set external-ip internal-ip). I'm really not even sure if I did that correctly, maybe it should be internal-ip then external-ip. Also, like I said earlier, it may not have made any difference at all. Seems like the alternate addresses would only affect my sever if it didn't have a direct connection to the internet anyway, but it may help the clients behind NAT on the LAN for all I know. I'm sure I'm probably opening up security holes in my network all over the place by trying to fix this, but I guess that's the cost of learning. Better at home than at work I guess. Once those changes were made, I rebooted. When my server came back up, IIS was pissed off and wouldn't accept connections. This was because the citrix xml service was started, and wouldn't allow IIS to start on the same address. I stopped the citrix xml service, and started IIS and now I was able to launch applications via NFuse. I think the problem may have been the citrix xml service all along, but yet again, I'm not sure. I thought that if you setup citrix to share the same port as IIS, that it's not suppsed to start up anyway.

So, I'm still hoping someone will help me with my original problem, but I'm not holding my breath. If anyone happens to try any of the steps I went through, I hope they don't end up worse than when they started. However, I wouldn't be surprised if that were the case.
 
You are not alone. I am having the same problem. From within the LAN I can connect to published Outlook either with Program Neigborhood or Nfuse. From outside I get the I/O errors, exactly as you described. Funny thing is that I can run the a full Citrix window from outside, just not the published apps.

JLG
 
Once again, I'm not sure which change I made to correct the problem, but I've managed to get everything working internally and externally to my LAN. The things that I changed are as follows, and you may want to try some of these settings if you have any differences:

1. For my applications settings, I use tcp/ip + http and made sure that I specify the port IIS is using for the port setting on the applications.

2. All applications are setup to contact my citrix server via it's external IP address. (actually I use my dns address, which resolves as the external IP from all clients)

3. My server is not behind a firwall, only my clients are (NAT). So, I removed any alternate addresses for my citrix server.

4. Citrix XML is setup to share port 8080 with IIS, and I made sure that the Citrix XML service wasn't registering.

5. When you right click on your server in CMC and choose properties, and go to the "MetaFrame Settings" tab, I have the box checked, that says "Server responds to ICA client broadcast messages".



I think that's about all I've changed, but I may be forgetting something. I know how annoying that error is, so if you have something set that I don't, I'll make the change, and see if it knocks out my connection as well, if you want. If you're behind a firewall, I won't be too much help though. I'll be installing a firewall sometime soon, so we'll see how that goes. I'm sure I'll be back crying when the time comes.
 
we're having the same.
ever since we went to published apps on remote desktops.
instead of custom connections for dial up users.seems to be something with seamless connection, if you have custom connection,looks like more stable. having said that we're haveing problems with our remote users they're all over the place at the moment.changed to using http only (related?)
might help nudge in the right direction
cheers
 
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