Why is this not working?

Im trying to get a list of available entries from ldap by simple filter: attribute cn must be less than 1000 and greater than 500. According to Net::LDAP documentation this could be done like this:

#!/usr/bin/env perl use strict; use warnings; use Net::LDAP; my $ldap = Net::LDAP->new(''); my $mesg = $ldap->bind('cn=root,dc=lomonosov,dc=parallel,dc=ru', passw +ord => 'rootpw'); $|=1; print "Searching for uids less than 1000 and gt 500... "; $mesg = $ldap->search( base => "ou=slurm,dc=lomonosov,dc=parallel,dc=ru", filter => "&(cn<=1000)(cn>=500)" ); $mesg->code && die $mesg->error; print "Ok\nFound: "; print join ", ", map $_->get_value("cn"), $mesg->entries;
But it produces:
Searching for uids less than 1000 and gt 500... Ok Found:
I know that there is a two hundred or so entries in ldap for this request,
fisher% ldapsearch -h -D "cn=root,dc=lomonosov,dc=parall +el,dc=ru" -w "rootpw" -b "ou=slurm,dc=lomonosov,dc=parallel,dc=ru" "& +(cn>600)(cn<1000)" |tail -3 # numResponses: 145 # numEntries: 144
In fact, the problem experienced on a simple filters with 'less than' or 'greater than' comparisions; complex search filters like '|(cn=527)(cn=528)' works just fine. What am I doing wrong? How can I get a list of entries with said filter?

Answer found, thanks to all. The original request using ldapsearch was wrong (according to rfc4515 there isn't '<' sign but '<='); the server doesn't answer for that type of comparisions becouse of absence of index.

In reply to Net::LDAP q by fisher

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