[ntp:questions] Need help for IPv6 setup

Nicolas Braud-Santoni nicolas.braudsantoni at gmail.com
Tue May 29 13:37:01 UTC 2012


Hi,

I noticed my NTP server isn't usable over IPv6, despite it being
pingable over IPv6.
I checked that it's not a firewall problem (actually disabled iptables
for checking this).

Here is ntp's configuration :
# /etc/ntp.conf, configuration for ntpd; see ntp.conf(5) for help
listen-on ipv4 accept
listen-on ipv6 accept

driftfile /var/lib/ntp/ntp.drift

# Peers[...]

setvar access_policy = "open access" default
restrict -4 default kod notrap nomodify nopeer noquery
restrict -6 default kod notrap nomodify nopeer noquery

# Local users may interrogate the ntp server more closely.
restrict 127.0.0.1
restrict ::1

Here is some relevant information :
# netstat -lp | grep ntp
udp        0      0 <mydomain>:ntp *:*
22047/ntpd
udp        0      0 localhost.localdoma:ntp
*:*                                 22047/ntpd
udp        0      0 *:ntp
*:*                                 22047/ntpd
udp6       0      0 [::]:ntp
[::]:*                              22047/ntpd

# ntpd --version
ntpd - NTP daemon program - Ver. 4.2.6p2

Here is a test from another IPv6-enabled box :

# ping6 2001:41d0:8:12c7::dead:bebe
PING 2001:41d0:8:12c7::dead:bebe(2001:41d0:8:12c7::dead:bebe) 56 data
bytes
64 bytes from 2001:41d0:8:12c7::dead:bebe: icmp_seq=1 ttl=61
time=0.480 ms
64 bytes from 2001:41d0:8:12c7::dead:bebe: icmp_seq=2 ttl=61
time=0.334 ms
[...]

# ntpdate -qd 2001:41d0:8:12c7::dead:bebe
29 May 15:28:32 ntpdate[17761]: ntpdate 4.2.6p2 at 1.2194-o Sun Oct 17
13:35:14 UTC 2010 (1)
transmit(2001:41d0:8:12c7::dead:bebe)
transmit(2001:41d0:8:12c7::dead:bebe)
transmit(2001:41d0:8:12c7::dead:bebe)
transmit(2001:41d0:8:12c7::dead:bebe)
transmit(2001:41d0:8:12c7::dead:bebe)
2001:41d0:8:12c7::dead:bebe: Server dropped: no data
server 2001:41d0:8:12c7::dead:bebe, port 123
stratum 0, precision 0, leap 00, trust 000
refid [2001:41d0:8:12c7::dead:bebe], delay 0.00000, dispersion
64.00000
transmitted 4, in filter 4
reference time:    00000000.00000000  Mon, Jan  1 1900  0:09:21.000
originate timestamp: 00000000.00000000  Mon, Jan  1 1900  0:09:21.000
transmit timestamp:  d36f4d87.176c5e40  Tue, May 29 2012 15:28:39.091
filter delay:  0.00000  0.00000  0.00000  0.00000
         0.00000  0.00000  0.00000  0.00000
filter offset: 0.000000 0.000000 0.000000 0.000000
         0.000000 0.000000 0.000000 0.000000
delay 0.00000, dispersion 64.00000
offset 0.000000

29 May 15:28:41 ntpdate[17761]: no server suitable for synchronization
found

The same thing happens in local, using either
2001:41d0:8:12c7::dead:bebe or ::1.

Would anyone have a clue ?

Thanks,
Nicolas



More information about the questions mailing list