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In our xrootd meeting today, we have determined that we need to change the directory naming convention used by xrootd/olbd for administrative files. Curently, the servers create files in /tmp to hold the process ID (i.e., pid files). The xrootd has no problems because it always qualifies it's pid file with it's port number. The olbd does not do so and so that precludes running more than one server and supervisor olbd on the same machine. The problem is worse for the olbd because it also creates management files in /tmp/.olbd and these are not qualified as well. One can get around these problems by explcitly specifying what the paths should be for these files but that is a nuisance and something most people forget until one or the other server can't start up. The xrootd pid file is not particularly important and, in fact, the server goes on it's merry what even if it can't create the file. However, it is useful when one want to figure out who is runniong what on the machine. The olbd pid file is more important since it not only holds the process id but also the local root prefix being used. This information is used by external application to add or remove filename prefixes. So, we need to rethink how directories are named to avoid collisions. I propose adding the "-n <name>" option to xrootd and olbd. The -n option allows you to automatically add <name> as a top-level directory qualifier to all directories used to create admin-type files. So, for instance, "xrootd -n prod" would place the pid file in "/tmp/prod". while "olbd -n prod" would place the pid file in "/tmp/prod" and the special files in "/tmp/prod/.olbd". This introduces a major restriction: The xrootd/olbd pair *must* use the same "-n" argument if they are running as a paired set of servers *and* the xrootd/olbd *must* run using the same username. However, you will be able to start as many xrootd/olbd pairs as you wish as long as each pair is assigned a different "name" using the "-n" option. Now for the hard questions: a) Should there be a default name? One proposal is to use the username as the default name. This introduces a hidden depndency in that if you do not run the xrootd/olbd under the same username, then it won't work at all. Whereas having no default allows them to work if they can work at all. Another proposal is to use the configuration file name as the default (well, atleat up to the dot in the name). This makes sense once you read the next question. b) Should the name be able to be specified in the config file? This makes sense in a way because it's likely that the that each name will have a different configuration file because of connection differences, let alone port number differences. Please let me know what you think of this arrangement. Feel free to suggest other alternatives. Andy