Andrew Wheadon writes:
 > When I take a look at last I usually find that more than
 > 62% of the machines logging into my machine have hostnames
 > that are longer than 16 charaters. How about increasing the
 > length to 32 or 64 or whatever:

That does not solve the problem.  The hostname can be of any length.
Either make the field variable-length or (my preference) just log the
IP-address and let last/who/whatever do the reverse mapping.

/assar