If you've been keeping up with my blog, we've had our share of issues with Domino 6.5.4 on iSeries. We've been experiencing hangs on our mail subsystem and we've also seen some issues with our Sametime subsystem as well. We have loaded two sets of iSeries fixes for those along with 2 system restarts (IPL). On 6/24/05, we performed an IPL.
For the Sametime issue, we have loaded not one, but two hotfixes that did not correct the problem. We finally determined that the Sametime issue was with the way the Notes 6.5.2+ Clients handle integrated presence awareness. We haven't had a Sametime problem (yet) since our IPL on 6/24, so it may turn out that one of the fixes may correct this issue yet... but I won't hold my breath.
We also went nearly 2 weeks without a problem with our mail server. But on Wednesday we had another hang on our mail subsystem and then we had another today. I've sent IBM more sets of debug data just for them to tell me again that it's just a network problem.
On the upside, I have learned a lot over the past month(s) in regards to some system troubleshooting. I have learned that Sametime for iSeries creates some pretty slick trace files that can be sent to IBM without having to collect the data yourself. I've worked a good bit with notes.ini settings for enabling debug parameters for TCP as well. I think one of the biggest lessons may be that it might not be so wise to stay on top of things so much. At the same time, though, some of my other Domino for iSeries colleagues have not been experiencing any issues with 6.5.4. I guess it goes to show that each shop is really unique and you never know if you'll have a good or bad experience with an upgrade. I still believe my philosophy is that you should try to stay really current because even though strange things can break, there are still many other fixes that can be helpful with upgrades!