Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

I'm making some tests with leapfile feature on ntpd to send fake leap-seconds and ensure our Linux platform is resilient to the "bug". The NTP lab is quite simple: a "master" server with local clock running ntpd with leapfile feature, and a "client" system also that connects to the "master".

I have just found that leap-second flag is forwarded from the "master" to the "client" without problems on CentOS-6 boxes (running 4.2.4p8-2), but with the same configuration it doesn't work on Debian Squeeze (4.2.6.p2+dfsg-1+b1).

If I query ntpd it returns "leap_add_sec" and "leap=01" flags, and running a tcpdump I also see those flags, but the "client" system is ignoring the flags, as I say: this only happens on Debian running 4.2.6.p2 from upstream, not on CentOS with 4.2.4p8.

CentOS master NTP config = works OK

driftfile /var/lib/ntp/drift
restrict default kod nomodify notrap nopeer noquery
restrict 127.0.0.1
server 127.127.1.0 iburst
fudge 127.127.1.0 stratum 10
includefile /etc/ntp/crypto/pw
keys /etc/ntp/keys
keysdir /etc/ntp
crypto pw password

Debian master NTP config = leap-second not forwarded from master to the client

leapfile "/etc/leap-seconds.list"
driftfile /var/lib/ntp/drift
restrict default kod nomodify notrap nopeer noquery
restrict 127.0.0.1
server 127.127.1.1 iburst
fudge 127.127.1.1 stratum 10
includefile /etc/ntp/crypto/pw
keys /etc/ntp/keys

The unique difference between CentOS and Debian config files is leap-second settings, it depends on ntpd version, the remaining conf is the same on both master and client servers.

This is the NTP config on the clients:

driftfile /var/lib/ntp/drift
restrict default kod nomodify notrap nopeer noquery
restrict 127.0.0.1
server 10.204.3.2 iburst
includefile /etc/ntp/crypto/pw
keys /etc/ntp/keys 

What can be the reason that blocks leap-second being forwarded on Debian/4.2.6.p2 systems?

share|improve this question

1 Answer 1

FYI: seems that it's a version specific behavior, with a "forward"-port package from Lenny (4.2.4p4+dfsg-8lenny3) on Squeeze works as expected: leap seconds fields are forwarded to the clients.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.