From: Trevor Daniels Date: Wed, 3 Mar 2010 00:39:11 +0000 (+0000) Subject: Docs: CG 2.4.6 Add warning about MTU in domestic router X-Git-Tag: release/2.13.15-1~12 X-Git-Url: https://git.donarmstrong.com/?a=commitdiff_plain;h=72b40d872ba61f7542b97600d8169528e5e9357c;p=lilypond.git Docs: CG 2.4.6 Add warning about MTU in domestic router --- diff --git a/Documentation/contributor/source-code.itexi b/Documentation/contributor/source-code.itexi index b27228d2f3..27e30b165a 100644 --- a/Documentation/contributor/source-code.itexi +++ b/Documentation/contributor/source-code.itexi @@ -1452,6 +1452,31 @@ should add these lines to @file{.git/config}: @end example @end itemize +@knownissues +Encryption protocols, including ssh, generally do not permit packet +fragmentation to avoid introducing a point of insecurity. This +means that the maximum packet size must not exceed the smallest +MTU (Maximum Transmission Unit) set in the routers along the path. +This smallest MTU is determined by a procedure during call set-up +which relies on the transmission over the path of ICMP packets. +If any of the routers in the path block ICMP packets this mechanism +fails, resulting in the possibility of packets being transmitted +which exceed the MTU of one of the routers. If this happens the +packet is discarded, causing the ssh session to hang, timeout or +terminate with the error message + +@example +ssh: connect to host port 22: Bad file number +fatal: The remote end hung up unexpectedly +@end example + +depending on precisely when in the proceedings the first large +packet is transmitted. Most routers on the internet have MTU +set to 1500, but routers installed in homes to connect via +broadband may use a slightly smaller MTU for efficient transmission +over ATM. If this problem is encountered a possible work-around is +to set the MTU in the local router to 1500. + @node Git on Windows @section Git on Windows