[Bug 1257082] Re: MAAS does not use NTP servers specified in DHCPD options
Robie Basak
1257082 at bugs.launchpad.net
Mon Dec 16 12:48:53 UTC 2013
Setting to Medium priority as a workaround is available.
Debian is considering making NTP available by default in
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=731594.
I'm also concerned that though changing NTPDATE_USE_NTP_CONF to default
to "no" if /etc/ntp.conf doesn't exist seems to be right solution right
now, it may have a negative impact to non-MAAS users, and so this needs
to be considered carefully.
So it seems like we're still figuring out what the right solution should
be. Some discussion in Ubuntu at: https://lists.ubuntu.com/archives
/ubuntu-devel/2013-December/037895.html
Given that there's a workaround, I think we should probably wait to see
what Debian wants to do with ntp by default before we tackle this. If
this takes too long, then I suppose we could patch the behaviour above,
or even send that to Debian.
** Description changed:
+ [Impact]
+
+ MAAS-deployed systems *that do not have persistent RTCs* (unusual) have
+ difficulty with time and authentication, generally making these nodes
+ unusable.
+
+ [Workaround]
+
+ See comment #8.
+
+ [Original Description]
+
I have tried setting up NTP servers as DHCP options to MAAS nodes
because I am behind a proxy here at work that cannot contact
ntp.ubuntu.com. Here is the top of the dhcpd.conf file on on my MAAS
head node, maas01:
root at maas01:/etc/dhcp# less dhcpd.conf
default-lease-time 600;
max-lease-time 7200;
subnet 192.168.0.0 netmask 255.255.0.0 {
- option domain-name "mgmt";
- option domain-name-servers 192.168.255.254;
- option routers 192.168.255.254;
+ option domain-name "mgmt";
+ option domain-name-servers 192.168.255.254;
+ option routers 192.168.255.254;
- pool {
- range 192.168.0.1 192.168.255.253;
- deny unknown-clients;
- }
+ pool {
+ range 192.168.0.1 192.168.255.253;
+ deny unknown-clients;
+ }
}
subnet 10.255.0.0 netmask 255.255.0.0 {
- option domain-name "maas";
- option domain-name-servers 10.255.0.1;
- option routers 10.255.0.1;
- option ntp-servers 172.31.22.1, 172.31.23.1, 172.31.20.104;
- next-server 10.255.0.1;
+ option domain-name "maas";
+ option domain-name-servers 10.255.0.1;
+ option routers 10.255.0.1;
+ option ntp-servers 172.31.22.1, 172.31.23.1, 172.31.20.104;
+ next-server 10.255.0.1;
- pool {
- range 10.255.1.0 10.255.255.254;
- deny unknown-clients;
- }
+ pool {
+ range 10.255.1.0 10.255.255.254;
+ deny unknown-clients;
+ }
}
I have also verified the parameter is being sent to a client’s DHCP
lease:
ubuntu at sled204n0:/var$ cat /var/lib/dhcp/dhclient.eth0.leases
lease {
- interface "eth0";
- fixed-address 10.255.4.44;
- option subnet-mask 255.255.0.0;
- option routers 10.255.0.1;
- option dhcp-lease-time 600;
- option dhcp-message-type 5;
- option domain-name-servers 10.255.0.1;
- option dhcp-server-identifier 10.255.0.1;
- option ntp-servers 172.31.22.1,172.31.23.1,172.31.20.104;
- option domain-name "maas";
- renew 4 2000/01/06 19:40:51;
- rebind 4 2000/01/06 19:40:51;
- expire 4 2000/01/06 19:40:51;
+ interface "eth0";
+ fixed-address 10.255.4.44;
+ option subnet-mask 255.255.0.0;
+ option routers 10.255.0.1;
+ option dhcp-lease-time 600;
+ option dhcp-message-type 5;
+ option domain-name-servers 10.255.0.1;
+ option dhcp-server-identifier 10.255.0.1;
+ option ntp-servers 172.31.22.1,172.31.23.1,172.31.20.104;
+ option domain-name "maas";
+ renew 4 2000/01/06 19:40:51;
+ rebind 4 2000/01/06 19:40:51;
+ expire 4 2000/01/06 19:40:51;
}
Even so, the date on the target node is still incorrect.
ubuntu at sled204n0:/etc$ date
Thu Jan 6 19:52:29 UTC 2000
The ntpdate defaults are the following (unchanged from MAAS defaults):
ubuntu at sled204n0:/etc$ cat /etc/default/ntpdate
# The settings in this file are used by the program ntpdate-debian, but not
# by the upstream program ntpdate.
# Set to "yes" to take the server list from /etc/ntp.conf, from package ntp,
# so you only have to keep it in one place.
NTPDATE_USE_NTP_CONF=yes
# List of NTP servers to use (Separate multiple servers with spaces.)
# Not used if NTPDATE_USE_NTP_CONF is yes.
NTPSERVERS="ntp.ubuntu.com"
# Additional options to pass to ntpdate
NTPOPTIONS=""
And the DHCP generated NTP server file is correct:
ubuntu at sled204n0:/etc$ cat /var/lib/ntpdate/default.dhcp
# NTP server entries received from DHCP server
NTPSERVERS='172.31.22.1 172.31.23.1 172.31.20.104'
The culprit seems to be in how ntpdate-debian is programmed. the logic
ignores /var/lib/ntpdate/default.dhcp if /etc/default/ntpdate sets
NTPDATE_USE_NTP_CONF=yes (the default).
After examining the script further my recommendation would be for the
/etc/dhcp/dhclient-exit-hooks.d/ntpdate to create the file
/var/lib/ntp/ntp.conf.dhcp. By doing so ntpdate-debian will work
transparently with /etc/defaults/ntpdate and NTP servers advertised by
DHCPD.
-
-------------------------------------------------------------------------
(contents of /var/log/maas/* is 125MB in size, will post data from there if requested)
# dpkg -l '*maas*'|cat
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-==================================-======================================-============-==========================================================================
ii maas 1.3+bzr1461+dfsg-0ubuntu2.2+tay.8 all Ubuntu MAAS Server
ii maas-cli 1.3+bzr1461+dfsg-0ubuntu2.2+tay.8 all Ubuntu MAAS Client Tool
ii maas-cluster-controller 1.3+bzr1461+dfsg-0ubuntu2.2+tay.8 all Ubuntu MAAS Cluster Controller
ii maas-common 1.3+bzr1461+dfsg-0ubuntu2.2+tay.8 all Ubuntu MAAS Server
un maas-dhcp <none> (no description available)
un maas-dns <none> (no description available)
ii maas-region-controller 1.3+bzr1461+dfsg-0ubuntu2.2+tay.8 all Ubuntu MAAS Server
ii python-django-maas 1.3+bzr1461+dfsg-0ubuntu2.2+tay.8 all Ubuntu MAAS Server - (django files)
ii python-maas-client 1.3+bzr1461+dfsg-0ubuntu2.2+tay.8 all Ubuntu MAAS API Client - (python files)
ii python-maas-provisioningserver 1.3+bzr1461+dfsg-0ubuntu2.2+tay.8 all Ubuntu MAAS Server
** Bug watch added: Debian Bug tracker #731594
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=731594
** Changed in: ntp (Ubuntu)
Importance: High => Medium
--
You received this bug notification because you are a member of Ubuntu
Server Team, which is subscribed to ntp in Ubuntu.
https://bugs.launchpad.net/bugs/1257082
Title:
MAAS does not use NTP servers specified in DHCPD options
To manage notifications about this bug go to:
https://bugs.launchpad.net/maas/+bug/1257082/+subscriptions
More information about the Ubuntu-server-bugs
mailing list