Bug 2531

Summary:	MaxSessions config parameter name is highly ambigious
Product:	Portable OpenSSH	Reporter:	DarkTrick <DarkTrick>
Component:	sshd	Assignee:	Assigned to nobody <unassigned-bugs>
Status:	CLOSED FIXED
Severity:	normal	CC:	djm, jjelen
Priority:	P5
Version:	7.1p1
Hardware:	All
OS:	Linux
Bug Depends on:
Bug Blocks:	2451

Description DarkTrick 2016-01-24 01:00:47 AEDT

The MaxSessions config parameter for the sshd-conf file let the user assume, that this parameter will limit the maximal sessions possible through ssh (this is also what conclusion the explanation of the parameter would lead to).
However, regarding to the changelog it has a slightly different meaning (see changelog)

My Suggestions:
Change the name of the entry or change the resulting behaviour.

Comment 1 Jakub Jelen 2016-01-25 18:22:50 AEDT

*** Bug 2532 has been marked as a duplicate of this bug. ***

Comment 2 Jakub Jelen 2016-01-25 18:35:26 AEDT

> MaxSessions
>     Specifies the maximum number of open sessions permitted per network connection.  The default is 10.

Manual page seems for me enough straightforward. Do you have any specific proposal what would you like to change?

Changing name of configuration option is not a good idea once it was released and is widely used. For the record, it was added 8 years ago in
https://github.com/openssh/openssh-portable/commit/7207f64a23a49a719aad3083c068f50e5034ccb8

Comment 3 DarkTrick 2016-01-25 23:39:14 AEDT

ow, I didn't know, that it was added 8 years ago. Never checked the date. So renaming of cause is not an option.

I would suggest to make it clear, that this is about multiplexing of *one* connection and not about the number of connections.

My suggestion would be to also add the following part of the changelog:
------------------------
This is useful for disabling login/shell/subsystem access while leaving port-forwarding working (MaxSessions 0), disabling connection multiplexing (MaxSessions 1) or simply increasing the number of allows multiplexed sessions.
------------------------

TBH, I don't know how to make a short sentence, that would sound nice and express, the difference. But (at least I think) that part of the changelog makes things more clear. In case someone thought about the maximum number of connections, he will then understand, that this is something different to what he's searching.

Comment 4 Damien Miller 2016-02-05 13:38:01 AEDT

I've changed it to make it more clear what it applies to.

MaxSessions
    Specifies the maximum number of open shell, login or subsystem
    (e.g. sftp) sessions permitted per network connection.  Multiple
    sessions may be established by clients that support connection
    multiplexing.  Setting MaxSessions to 1 will effectively disable
    session multiplexing, whereas setting it to 0 will prevent all
    shell, login and subsystem sessions while still permitting
    forwarding.  The default is 10.

Comment 5 Damien Miller 2016-08-02 10:42:18 AEST

Close all resolved bugs after 7.3p1 release