networking.service hangs on shutdown -- killing dhclient has no effect any more
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
bind9 (Ubuntu) |
Fix Released
|
High
|
LaMont Jones | ||
isc-dhcp (Ubuntu) |
Fix Released
|
High
|
Unassigned |
Bug Description
On current xenial, LXD containers take ages to reboot:
lxc launch images:
lxc exec x1 reboot
"systemctl list-jobs" shows:
117 networking.service stop running
root@x1:~# systemctl status networking
● networking.service - Raise network interfaces
Loaded: loaded (/lib/systemd/
Drop-In: /run/systemd/
Active: deactivating (stop-sigterm) since Fri 2016-03-11 16:03:51 UTC; 21s ago
Docs: man:interfaces(5)
Process: 187 ExecStop=
Process: 55 ExecStart=
Process: 49 ExecStartPre=
Main PID: 55 (code=exited, status=0/SUCCESS)
Tasks: 1 (limit: 512)
CGroup: /system.
└─146 /sbin/dhclient -1 -v -pf /run/dhclient.
Mar 11 16:03:52 x1 dhclient[207]: For info, please visit https:/
Mar 11 16:03:52 x1 dhclient[207]:
Mar 11 16:03:52 x1 dhclient[207]: Listening on LPF/eth0/
Mar 11 16:03:52 x1 ifdown[187]: Listening on LPF/eth0/
Mar 11 16:03:52 x1 ifdown[187]: Sending on LPF/eth0/
Mar 11 16:03:52 x1 ifdown[187]: Sending on Socket/fallback
Mar 11 16:03:52 x1 dhclient[207]: Sending on LPF/eth0/
Mar 11 16:03:52 x1 dhclient[207]: Sending on Socket/fallback
Mar 11 16:03:52 x1 dhclient[207]: DHCPRELEASE on eth0 to 10.0.3.1 port 67 (xid=0x6480ef2b)
Mar 11 16:03:52 x1 ifdown[187]: DHCPRELEASE on eth0 to 10.0.3.1 port 67 (xid=0x6480ef2b)
The above is also the last journal line that I get for the usual 90s timeout, then the container finally reboots.
Not many processes are actually running any more:
root 1 0.0 0.0 37076 5304 ? Ss 16:03 0:00 /sbin/init
root 38 0.0 0.0 41572 3316 ? Ss 16:03 0:00 /lib/systemd/
root 41 0.0 0.0 35276 5668 ? Ss 16:03 0:00 /lib/systemd/
root 146 0.0 0.0 181376 2664 ? Ss 16:03 0:00 /sbin/dhclient -1 -v -pf /run/dhclient.
but apparently the dhclient instance refuses to die (note that ifdown -a itself is not running any more).
affects: | ifupdown (Ubuntu) → isc-dhcp (Ubuntu) |
Changed in isc-dhcp (Ubuntu): | |
assignee: | Martin Pitt (pitti) → nobody |
tags: | added: regression-release xenial |
Changed in isc-dhcp (Ubuntu): | |
assignee: | nobody → Martin Pitt (pitti) |
summary: |
- networking.service hangs on shutdown -- ifdown fails to kill dhclient + networking.service hangs on shutdown -- killing dhclient has no effect + any more |
Changed in bind9 (Ubuntu): | |
status: | Triaged → Fix Committed |
This is actually unrelated to rebooting -- "ifdown -a" returns immediately and leaves eth0 DOWN, but does not kill dhclient despite saying "Killed old client process".