From mboxrd@z Thu Jan 1 00:00:00 1970 From: Szymon Miotk Date: Fri, 18 Mar 2005 08:39:27 +0000 Subject: [LARTC] ARP queries generating entries in routing cache Message-Id: <423A93BF.8070908@crocom.com.pl> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lartc@vger.kernel.org Hello! I've noticed a strange thing: when a client system generates an arp query for an unexistent host, the routing cache entry is being made. My system is Fedora 2 with vanilla 2.6.11. the client is 10.1.1.2 with mask 255.255.0.0 the router/firewall is 10.1.1.1 with mask 255.255.255.0 Yes, the masks are different and this cannot be fixed easily. So, when the client generates ARP query for an unexistent host in 10.1.1.0/24 network everything is fine - query is dropped. But when it asks for something like 10.1.44.4, then the router drops the query, but an entry in routing cache is being made. This is a serious problem, because when someone has a virus which tries to spread itself, it generates thousands ARP queries per second and my routing cache overflows and the traffic crawls. did anybody meet such a problem? Szymon Miotk PS. The routing is configured ok. No are in arp cache, only routing cache is being affected. _______________________________________________ LARTC mailing list LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc