Directory listing fails for specific user

Darren Tucker dtucker at
Mon May 23 15:49:20 AEST 2016

On Mon, May 23, 2016 at 3:37 PM, Philipp Marek <philipp.marek at>

> [...]
> PMTU detection goes wrong, and the specific user has a directory with too
> many entries?
> Try to list /usr/bin/ as various users, and/or reduce the MTU for testing.

Another useful indicator: while the connection is in the hung state, run
"netstat" on both ends and figure out which line corresponds to the hung

If the "SendQ" entry (on the server side, probably) is non-zero and
non-decreasing that indicates that TCP can't deliver the packets, in which
case it's probably an MTU black hole.

Darren Tucker (dtucker at
GPG key 8FF4FA69 / D9A3 86E9 7EEE AF4B B2D4  37C9 C982 80C7 8FF4 FA69
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.

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