Any gotchas when migrating from HP UX to Linux?

We moved from HP-UX to Linux. I don’t think there were any big gotchas. We are using VMware, so we depend on that for our hardware redundancy instead of OS level high availability solutions. We had to switch to a PAE kernel in order to have more than 4GB RAM available on the system.

Another thing is you might have to adjust your ephemeral port range. On HP-UX this is supposed to be set in /etc/rc.config.d/nddconf. On Linux this is set in /etc/sysctl.conf (net.ipv4.ip_local_port_range).

This setting specifies what range to use as the local port number on outbound TCP/IP connections. You need to make sure the range is adequately large and that it doesn’t conflict with the server port numbers of any of your listening interfaces.

Another thing we had problems with was SELinux. It was shutting down Cloverleaf processes because it didn’t know how they were supposed to behave. I think you can either define an SELinux policy for Cloverleaf or do what we did which is to put SELinux into permissive mode.

We moved from AIX to RHEL.

There were a few minor updates we had to do to our scripts that interfaced with cloverleaf, mainly just differences in parameters for some *nix commands. Cloverleaf and all its scripts worked correctly.

You may need to up the semaphore count. we upped ours to:

sysctl -w kernel.sem=”1024 32000 1000 8192″

Also need to update: /etc/sysctl.conf

you’ll need to install the 32-bit libraries, since cloverleaf currently only supports 32 bit for versions up to 5.8. (6.0 looks like it supports 64 bit according to the release notes).

What version of cloverleaf are you planning on using on linux?

If you go up to 5.8, just be wary of the change to utf-8 encoding. we had some issues with feeds that used characters outside the standard ascii range. To get around this need to play with the encoding for the thread and be careful with any translation.

We had a couple issues where a lab system was sending a degree symbol and when processing pdf documents.

Hi all,  

Although we don’t have specific plans from moving away from IBM / AIX based hardware, we would be interested in hearing from any of you regarding why you made the switch to (presumably) intel / vmware from others.  Did anyone do this from IBM hardware?  Was it better fail over capabilities (shorter recovery time?) or other reasons?     Also, any comments regarding improved (or different) reliability would be welcome.

We may perhaps consider something like this for our test systems as the availability of our test environments are becoming just as important as production, especially during weekdays.

If this is better to have a separate thread for this, I can do that as well.

Thanks

Karl

We need to leave our HP-UX Itanium platform, as there will be (or already is) no longer support on the OS and Cloverleaf doesn’t support HP-UX Itanium anymore since 5.7 rev 3. As the HP-UX platform is very stable, but also very costly, we are looking for something less expensive, without losing out on stability.

We have been considering Windows and (RHE) Linux. We like Linux better because it has a lock manager per site, enough support (Windows as well of course), seems to be very stable and we will have less problems converting our HP-UX related tcl-procs to Linux.