On Wednesday 11 July 2007 14:19:09 Eric F Crist wrote: > <snip> > What should I look for? Is there possibly some weird caching issues > at their ISPs? How can I fix this?
Do a tcpdump when someone connects from their network and check for TCP-MSS issues, which would be my first guess when small files/items load fine over HTTP but items larger than a single TCP-packet won't (which basically fits the symptoms you describe). As some ISPs will do IP fragmentation when a packet too large to fit over the downlink to a customer arrives, you'll not see this problem with these. Those ISPs that don't do IP fragmentation on the downlink (quite a few) generally should send out an ICMP-message with a "Fragmentation needed" error (which appears in the tcpdump), but some don't do that either. Generally, the MSS in their SYN-packet when connecting to your webserver should be below 1460; most probably at 1452 (which is DSL and cable AFAIK), or more generally speaking (their) MTU-40, and the _IP_ packet size your host sends back should always be equal to or below the minimum of your MSS (which is sent in the SYN/ACK packet) and their MSS, plus 40. If this is not the case, you have an issue. -- Heiko Wundram Product & Application Development ------------------------------------- Office Germany - EXPO PARK HANNOVER Beenic Networks GmbH Mailänder Straße 2 30539 Hannover Fon +49 511 / 590 935 - 15 Fax +49 511 / 590 935 - 29 Mail [EMAIL PROTECTED] Beenic Networks GmbH ------------------------------------- Sitz der Gesellschaft: Hannover Geschäftsführer: Jorge Delgado Registernummer: HRB 61869 Registergericht: Amtsgericht Hannover _______________________________________________ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"