[ic] Possible bug: Too many new ID assignments for this IP address

John1 list_subscriber at yahoo.co.uk
Sun Dec 19 17:20:49 EST 2004

In October I posted
explaining what I thought was a bug which can result in *permanently*
blocked access to Interchange sites from ISPs who use proxy servers.

To avoid this problem we are currently running with "RobotLimit 0".

A full explanation of the problem and what I believe is the cause can be
found at

Here is a snippet:

The reason for this is that the check to see whether the addr_ctr file
should be expired is only made if RobotLimit has been exceeded.  And then,
the addr_ctr file is only deleted if the modify date is older than a day
(the default for MV_ROBOT_EXPIRE).

So, here is the problem:  any IP address that is typically allocated more
than 1 session id in a 24 hr period will never get its addr_ctr file
expired.  i.e.  There needs to be a full 24 hr period without access from
the same IP address before the addr_ctr file will be deleted thus
re-allowing access from that IP address.  For large ISPs using a relatively
small number of proxy servers this may never happen, and so access from
their proxy servers is permanently blocked.

I know very little Perl so I am not right person to fix the code, but I will
be happy to contribute to any discussion on possible solutions.


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