mental ray Standalone Hang Tips

Ever get stuck trying to run the mental ray standalone executable after a fresh install, or moving a machine, or re-organizing a group of distributed render servers? Is the ray executable just hanging, and you can't figure out why? You suspect that its probably a machine network issue, but don't know where to start? Here's a few things to check:

1. First, try 'ray -version' from a command shell.
   This option does not try to connect to a license server, as it lists the version of mental ray and copyright information.
2. Then, try 'ray -h' or 'ray -v' from a command shell.
   The first should give you a list of ray command options, the second should list out the initial ray version information and then wait at the shell for input. I'm guessing that if you're really stuck nothing happens when you try either of these two.
3. Check to see if you are using NIS, or DNS.
   A hang can occur if your machine thinks it should be using one of these, but has no NIS or DNS server on its network. Or maybe, it can't find the nameserver you've specified. In fact you, or your sysadmin, may have used rayinstall, or some similar installation tool, and ignored messages about such things, thinking it was taken care of for you, as you proceeded. Or maybe, the network configuration has changed since you did the install. Useful files to check in Linux are:
   • /etc/resolve.conf
   • /etc/nsswitch.conf
   • /etc/hosts
   or you can use the System Settings -> Network menu from the GUI
4. Try 'strace'.
   If you are on Linux, you can verify your problem by using this invaluable tool to track what's happening when you get stuck. For example, type 'strace ray -v' in the shell, and you may see that your are stuck in a loop hanging on trying to find the nameserver IP address. Check the address its trying to find, and see if that makes sense with your network plan.
5. Try 'spmstat'.
   Check to see if you can see your license server separately from the ray executable. Often this is installed in the bin directory. For more details, see the spm installation instructions. There are also a variety of GUIs offered by the 3D application vendors who support standalone licenses to check your license connection from the machine you're trying to run on.