Hello > The MTU is 1500. The ADSL Router adds 8 bits for > encapsulation for PPPoE, this gives a total of 1508. Since > this is more than the 1500, the packet doesnt go thru. The > solution is to reduce the MTU size (on the MS Exchange Machine?) > to 1492.
I had the same exactly the same problem with some gre-tunnels over a cable environment. The funny thing was only very little traffic did not pass thuru the tunnel. I found two scenarios for this. First: it was traffic which gone first thuru a watchguard firewall. Since the set a df-bit to every packet some bigger packets were unable to come thuru. This problem occured on point-to-point connections over the cablenetwork. Second: was mostly the same as the first but from the internet into the network thuru a tunnel. The best candidate for testing was the bluewin homepage (sorry, alain) since their traffic seemed to come always set with df for some time. This has been changed about a three-quarter year ago as far as i can remember. The only solution was a command called 'ip mtu 1500' which instructs the router to fragment tunnel-traffic even when there is a df-bit set. This command is available in 12.1.5T and above. I suspect this is not a solution in your case but maybe it gives you hint where to search for your issues. I had to go on site with a lan-analyzer for quite some time so find that out. Have nice holidays. -- Kind regards, Roman Hochuli GPS-Technik AG Z�rcherstrasse 139 8952 Schlieren Switzerland Tel +41-1-7329977 Fax +41-1-7311840 X-NCC-RegID: ch.gps ---------------------------------------------- [EMAIL PROTECTED] Maillist-Archive: http://www.mail-archive.com/swinog%40swinog.ch/
