Bug 184389

Summary: [libalias] libalias fails to adjust MTU from jails
Product: Base System Reporter: Rudy <crapsh>
Component: kernAssignee: freebsd-bugs (Nobody) <bugs>
Status: Open ---    
Severity: Affects Only Me    
Priority: Normal    
Version: 9.2-RELEASE   
Hardware: Any   
OS: Any   

Description Rudy 2013-11-30 10:00:00 UTC 
	MTU size is not properly discovered from packets generated from jails.  libalias and/or ipfw_nat
	need to communicate with the network stack to determine MTU.

Fix: 

Set the MTU to 1476 on the interface connecting computer A to computer B.
How-To-Repeat: 	Set up ipfw_nat to nat packets generated from a jail.
	Send those packets to a second FreeBSD box that has a GRE tunnel to third machine.
	Attempt to ssh or scp a file larger than 1500 bytes from the jail to the third machine -- it hangs.
	If you SSH from the host (outside of the jail), the ssh connects.
	If you quickly log into the jail, it will briefly work (OS remembers MTU size for that path).
Comment 1 Mark Linimon freebsd_committer freebsd_triage 2014-05-04 06:14:51 UTC 
Responsible Changed
From-To: freebsd-bugs->freebsd-net

Over to maintainer(s).
Comment 2 Eitan Adler freebsd_committer freebsd_triage 2017-12-31 08:00:15 UTC 
For bugs matching the following criteria:

Status: In Progress Changed: (is less than) 2014-06-01

Reset to default assignee and clear in-progress tags.

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