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  $udb = udebug(server => "hostName",
                port   => 7021
               );

=head1 DESCRIPTION

The B<udebug> function returns the status of the lightweight
Ubik process for the database server process identified by
the B<port> argument that is running on the database server
machine named by the B<server> argument. The output identifies
the machines where peer database server processes are running,
which of them is the synchronization site (Ubik coordinator),
and the status of the connections between them.

=head1 OPTIONS

=over

=item B<server>

Names the database server machine that is running the process
for which to collect status information. Provide the machine's
IP address in dotted decimal format, its fully qualified host
name (for example, B<fs1.abc.com>), or the shortest abbreviated
form of its host name that distinguishes it from other machines.
Successful use of an abbreviated form depends on the availability
of a name resolution service (such as the Domain Name Service
or a local host table) at the time the function is issued.

=item B<port>

Identifies the database server process for which to collect
status information, either by its process name or port number.
Provide one of the following values:

=over

=item *

B<buserver> or B<7021> for the Backup Server

=item *

B<kaserver> or B<7004> for the Authentication Server

=item *

B<ptserver> or B<7002> for the Protection Server

=item *

B<vlserver> or B<7003> for the Volume Location Server

=back

=item B<long>

Reports additional information about each peer of the machine
named by the B<server> argument. The information appears by
default if that machine is the synchronization site.

=back

=head1 OUTPUT

Returns a reference to a hash containing all of the collected data.
Below is a list of keys that the hash may contain:

=over

=item B<interfaceAddr>

A reference to an array containing the IP addresses that are
configured with the operating system on the machine specified
by the B<server> argument.

=item B<now>

The time according to the clock on the database server machine
specified by the B<server> argument, measured in seconds since the
Epoch (00:00:00 UTC, January 1, 1970). For correct Ubik operation,
the database server machine clocks must agree on the time.

=item B<lastYesHost>, B<lastYesTime> and B<lastYesClaim>

If the B<udebug> function was issues during the coordinator election
process and voting has not yet begun, this key will not exist.
Otherwise, this key indicates which peer this Ubik process last voted
for as coordinator (it can vote for itself). The key B<lastYesTime>
contains the time (in seconds since the Epoch), of the vote. The key
B<lastYesClaim> contains the time (in seconds since the Epoch) that the
Ubik coordinator requested confirming votes from the secondary sites.
Usually, the B<lastYesTime> and B<lastYesClaim> values are the same;
a difference between them can indicate clock skew or a slow network
connection between the two database server machines. A small difference
is not harmful.

=item B<localVersion>

A reference to a hash containing information about the current
version number of the database maintained by this Ubik process.
It has two entries:

=over

=item B<epoch>

This field is based on a timestamp that reflects when the database
first changed after the most recent coordinator election.

=item B<counter>

This field indicates the number of changes since the election.

=back

=item B<amSyncSite>, B<syncSiteUntil> and B<nServers>

Indicates whether the Ubik process is the coordinator or not.
If there are multiple database sites, and the B<server> argument