Bug 1510872

Summary: samba 4.6.2-11.el7_4: unreliable winbindd start with Type=notify and double forking
Product: Red Hat Enterprise Linux 7 Reporter: Alexey Dobriyan <adobriyan>
Component: sambaAssignee: Andreas Schneider <asn>
Status: CLOSED ERRATA QA Contact: Andrej Dzilský <adzilsky>
Severity: unspecified Docs Contact:
Priority: high    
Version: 7.6-AltCC: adzilsky, asn, gdeschner, ian.donaldson, jarrpa, lmiksik, peter.clark, rhack, toneata, tscherf
Target Milestone: rcKeywords: ZStream
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: samba-4.7.1-4.el7 Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of:
: 1686048 (view as bug list) Environment:
Last Closed: 2018-04-10 17:30:15 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 1686048    

Description Alexey Dobriyan 2017-11-08 11:15:31 UTC
Description of problem:

winbindd is shipped with the following .service file:

    Type=notify
    PIDFile=/run/winbindd.pid
    ExecStart=/usr/sbin/winbindd "$WINBINDOPTIONS"

Default WINBINDOPTIONS are empty string.

Internally winbindd does double fork and notifies systemd about main process
PID change at lib/util/become_daemon.c:become_daemon()

Apparently this confuses systemd as Type=notify daemons aren't supposed to double fork.

We got report from user which reboots system often and every once in a while winbindd doesn't actually start despite reporting OK status. Manual restart fixes the problem.

We got confirmation that using

    WINBINDOPTIONS="-F --no-process-group"

(and deleting PIDFile line for a good measure) makes winbindd startup reliable.



Version-Release number of selected component (if applicable):
samba-4.6.2-11.el7_4.src.rpm
et al




How reproducible:
rarely


Steps to Reproduce:
1. reboot machine until winbindd doesn't start

Actual results:


Expected results:
winbindd starts 100% reliably


Additional info:

Comment 2 Alexey Dobriyan 2017-11-08 11:21:00 UTC
smbd and nmbd should have the same problem as they call into become_daemon() as well.

Comment 3 Alexey Dobriyan 2017-11-08 11:22:21 UTC
> Additional info:

What happens is that systemd sends spurious SIGTERM in the middle of daemon start.

Comment 6 Andrej Dzilský 2017-12-18 13:55:21 UTC
This rare bug is Hard to even reproduce nor test. Sanity Only.

Comment 10 errata-xmlrpc 2018-04-10 17:30:15 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2018:0937