Re: ntpq: write to localhost failed: Network is unreachable

On Wed, Jun 16, 2010 at 07:07:07PM +0100, Matthew Seaman wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
> 
> On 16/06/2010 18:15:32, Anton Shterenlikht wrote:
> > On Wed, Jun 16, 2010 at 06:08:35PM +0100, Matthew Seaman wrote:
> >> -----BEGIN PGP SIGNED MESSAGE-----
> >> Hash: SHA1
> >>
> >> On 16/06/2010 17:59:10, Anton Shterenlikht wrote:
> >>> After a recent upgrade to r209156 I get this error:
> >>>
> >>> $ ntpq -p
> >>> ntpq: write to localhost failed: Network is unreachable
> >>>
> >>> Please advise
> >>
> >> What does 'ifconfig -a' and 'netstat -rn' say?
> > 
> > $ ifconfig -a
> > em0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
> >         options=209b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,WOL_MAGIC>
> >         ether 00:13:21:5b:05:1c
> >         inet 137.222.187.28 netmask 0xffffff00 broadcast 137.222.187.255
> >         inet6 fe80::213:21ff:fe5b:51c%em0 prefixlen 64 scopeid 0x1 
> >         nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
> >         media: Ethernet autoselect (1000baseT <full-duplex>)
> >         status: active
> > em1: flags=8802<BROADCAST,SIMPLEX,MULTICAST> metric 0 mtu 1500
> >         options=209b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,WOL_MAGIC>
> >         ether 00:13:21:5b:05:1d
> >         media: Ethernet autoselect (100baseTX <full-duplex>)
> >         status: active
> > lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384
> >         options=3<RXCSUM,TXCSUM>
> >         inet 127.0.0.1 netmask 0xff000000 
> >         inet6 ::1 prefixlen 128 
> >         inet6 fe80::1%lo0 prefixlen 64 scopeid 0x3 
> >         nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
> > 
> > $ netstat -rn
> > Routing tables
> > 
> > Internet:
> > Destination        Gateway            Flags    Refs      Use  Netif Expire
> > default            137.222.187.250    UGS         0    65512    em0
> > 127.0.0.1          link#3             UH          0      293    lo0
> > 137.222.187.0/24   link#1             U           0    10861    em0
> > 137.222.187.28     link#1             UHS         0        0    lo0
> > 
> > Internet6:
> > Destination                       Gateway                       Flags      Netif Expire
> > ::/96                             ::1                           UGRS        lo0
> > ::1                               ::1                           UH          lo0
> > ::ffff:0.0.0.0/96                 ::1                           UGRS        lo0
> > fe80::/10                         ::1                           UGRS        lo0
> > fe80::%em0/64                     link#1                        U           em0
> > fe80::213:21ff:fe5b:51c%em0       link#1                        UHS         lo0
> > fe80::%lo0/64                     link#3                        U           lo0
> > fe80::1%lo0                       link#3                        UHS         lo0
> > ff01:1::/32                       fe80::213:21ff:fe5b:51c%em0   U           em0
> > ff01:3::/32                       ::1                           U           lo0
> > ff02::/16                         ::1                           UGRS        lo0
> > ff02::%em0/32                     fe80::213:21ff:fe5b:51c%em0   U           em0
> > ff02::%lo0/32                     ::1                           U           lo0
> > 
> > 
> > 
> >>  What happens if you try and ping localhost?
> > 
> > $ ping -c5 localhost
> > PING localhost (127.0.0.1): 56 data bytes
> > 64 bytes from 127.0.0.1: icmp_seq=0 ttl=64 time=0.109 ms
> > 64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.103 ms
> > 64 bytes from 127.0.0.1: icmp_seq=2 ttl=64 time=0.060 ms
> > 64 bytes from 127.0.0.1: icmp_seq=3 ttl=64 time=0.059 ms
> > 64 bytes from 127.0.0.1: icmp_seq=4 ttl=64 time=0.059 ms
> > 
> > --- localhost ping statistics ---
> > 5 packets transmitted, 5 packets received, 0.0% packet loss
> > round-trip min/avg/max/stddev = 0.059/0.078/0.109/0.023 ms
> 
> Nothing obviously wrong there.  Perhaps ntpd is not running?
> (Not sure quite why that should cause an error message about
> reachability of localhost: I suppose it's not completely unreasonable
> though.)
> 
> If ntpd is running, then try restarting it.  If the problem still
> persists, then it looks like you've found a bug.

# ps ax | grep ntp
55043  ??  Rs     0:00.02 /usr/sbin/ntpd -c /etc/ntp.conf -p /var/run/ntpd.pid -f /var/db/ntpd.drif
55050   0  R+     0:00.00 grep ntp
# ntpq -p
ntpq: write to localhost failed: Network is unreachable
# /etc/rc.d/ntpd restart
Stopping ntpd.
Waiting for PIDS: 55043.
Starting ntpd.
# ps ax | grep ntp
55113  ??  Ss     0:00.02 /usr/sbin/ntpd -c /etc/ntp.conf -p /var/run/ntpd.pid -f /var/db/ntpd.drif
55127   0  R+     0:00.00 grep ntp
# ntpq -p
ntpq: write to localhost failed: Network is unreachable
# 

Matthew, many thanks for your help.
I still think it's much more likely
the error is due to my misconfiguration
than a bug. I think I've seen something
like this before, just can't find anything
in mail archives.

I'll try asking on _at_current list.

thanks again
anton

-- 
Anton Shterenlikht
Room 2.6, Queen's Building
Mech Eng Dept
Bristol University
University Walk, Bristol BS8 1TR, UK
Tel: +44 (0)117 331 5944
Fax: +44 (0)117 929 4423