Logging usage

BIRCH currently has a fairly simple method for logging usage. If the environment varialbe $BIRCH_LOGGING is set to 1, messages listing the userid and a date stamp will be written to local/admin/logins.log every time a BIRCH user logs in, and to gde.log each time a BIRCH user starts GDE. If $BIRCH_LOGGING=0, messages are not written. This is the default.

To log or not to log

  1. Logging will not work if the BIRCH filesystem is mounted read-only. If the filesystem containing BIRCH mounted read-only to other workstations, logging will not work, and setting BIRCH_LOGGING to 1 may prevent users from logging in! logins.log and gde.log have the permissions rw-rw-rw-, meaning that they are world-writeable. However, on a read-only filesystem,
  2. Privacy/security considerations. Since logins.log and gde.log must be world-readable, anyone with login access to the system could read these files. In practice, they reveal no information other than the userid and time of login for users, so their potential usefulness for illicit purposes is dubious.

Turning on logging

Once again: do not turn on logging unless the BIRCH filesystem is mounted read-write to all workstations/servers!

That being said,  uncomment the following lines

local.cshrc.source local.profile.source

# setenv BIRCH_LOGGING 1


Collating the logging data

So far, there is only a crude method for collating the data. To find out the number of BIRCH users recorded in logins.log, go to the local/admin directory and type:

{mira:/home/psgendb/local/admin}birchstats logins.log
Number of logins:  18128 logins.log
Number of users:  109

The number of logins is the total number of times anyone has logged in. The number of users is the number of unique userids found in logins.log.

Similarly, to find the number of  users of GDE,

{mira:/home/psgendb/local/admin}birchstats gde.log
Number of logins:  3816 gde.log
Number of users:  65

Obviously, this mechanism could be a bit more sophisticated.

The right way to do this

There are a number of  remote method protocols that would provide a more secure logging mechanism, and that would probably get around the need to mount the BIRCH filesystem read-write. The big problem with these approaches, aside from their complexity, is that they place more demands upon the BIRCH Administrator to know how to implement them, and make more assumptions about the system being used. For now, this mechanism will have to suffice.

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