Bug 748726

Summary: Kernel compiled without legacy PTY support breaks xl2tpd/pppd
Product: [Fedora] Fedora Reporter: Steven Bakker <sb>
Component: kernelAssignee: Kernel Maintainer List <kernel-maint>
Status: CLOSED NOTABUG QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: unspecified    
Version: 16CC: gansalmon, itamar, jonathan, kernel-maint, madhu.chinakonda, paullee0
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-10-26 07:37:17 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:

Description Steven Bakker 2011-10-25 07:35:00 UTC 
Description of problem:

Trying to get an L2TP/IPsec tunnel to work; xl2tpd cannot start pppd, and the logs show:

--
Oct 25 09:23:48 cluestix xl2tpd[9040]: getPtyMaster_ptmx: unable to grantpt() on pty
Oct 25 09:23:48 cluestix xl2tpd[9040]: getPtyMaster: failed to use pts -- using legacy ptys
Oct 25 09:23:48 cluestix xl2tpd[9040]: getPtyMaster_pty: No more free pseudo-tty's
Oct 25 09:23:48 cluestix xl2tpd[9040]: start_pppd: unable to allocate pty, abandoning!
--

Turns out that the kernel is compiled without CONFIG_LEGACY_PTYS:

--
$ grep CONFIG_LEGACY /boot/config-3.1.0-0.rc10.git0.1.fc16.x86_64
# CONFIG_LEGACY_PTYS is not set
--

Version-Release number of selected component (if applicable):

kernel-3.1.0-0.rc10.git0.1.fc16.x86_64

How reproducible:

Always.


Steps to Reproduce:
1. Start xl2tpd
2. Try to set up a ppp tunnel
  
Actual results:

Failure, log messages as above.

Expected results:

A functional ppp0 interface.

Additional info:
Comment 1 Steven Bakker 2011-10-26 07:37:17 UTC 
Just realised the problem with xl2tpd lies somewhere else: the second log line gives an indication. It's something to do with /dev/pts permissions.

In fact, if I completely disable SELinux I have no problems with xl2tpd or pppd.

Sorry for the red herring.

-- Steven
Comment 2 paul 2012-01-24 16:16:45 UTC 
This is related to Bug 748724 


(I have almost exactly the same problem - xl2tpd-1.3.1-1.fc16.i686

Similar setup in Fedora 8 works without problem.

Jan 24 20:20:35 p320g--f16 xl2tpd[7002]: Connection established to
192.168.0.98, 1701.  Local: 32045, Remote: 1 (ref=0/0).  LNS session is
'default'
Jan 24 20:20:35 p320g--f16 xl2tpd[7002]: getPtyMaster_ptmx: unable to open
/dev/ptmx to allocate pty
Jan 24 20:20:35 p320g--f16 xl2tpd[7002]: getPtyMaster: failed to use pts --
using legacy ptys
Jan 24 20:20:35 p320g--f16 xl2tpd[7002]: getPtyMaster_pty: No more free
pseudo-tty's
Jan 24 20:20:35 p320g--f16 xl2tpd[7002]: start_pppd: unable to allocate pty,
abandoning!    
...