resolver change?

Did something change in our resolver / getaddrinfo() recently?  Check
this out:

des_at_soe ~% cat /etc/ntp.conf
server europe.pool.ntp.org iburst
server europe.pool.ntp.org iburst
server europe.pool.ntp.org iburst
server europe.pool.ntp.org iburst
server europe.pool.ntp.org iburst
server europe.pool.ntp.org iburst
des_at_soe ~% ntpq -pn
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
 81.169.180.26   .INIT.          16 u    -  512    0    0.000    0.000 4000.00
 81.169.180.26   .INIT.          16 u    -  512    0    0.000    0.000 4000.00
 81.169.180.26   .INIT.          16 u    -  512    0    0.000    0.000 4000.00
 81.169.180.26   .INIT.          16 u    -  512    0    0.000    0.000 4000.00
 81.169.180.26   .INIT.          16 u    -  512    0    0.000    0.000 4000.00
*81.169.180.26   192.53.103.104   2 u    2   64   77   63.218  -19.045   3.331

europe.pool.ntp.org returns a different address every time you query it,
and this used to work correctly.  I don't know when it changed; it
worked fine before I last rebooted my NTP server five days ago, but its
userland is from December 16.

It is *not* a name server issue:

des_at_soe ~% host europe.pool.ntp.org
europe.pool.ntp.org has address 81.169.180.26
europe.pool.ntp.org has address 77.66.32.156
europe.pool.ntp.org has address 217.8.241.75
europe.pool.ntp.org has address 130.226.232.145
europe.pool.ntp.org has address 87.32.0.19
des_at_soe ~% host europe.pool.ntp.org
europe.pool.ntp.org has address 87.32.0.19
europe.pool.ntp.org has address 81.169.180.26
europe.pool.ntp.org has address 77.66.32.156
europe.pool.ntp.org has address 217.8.241.75
europe.pool.ntp.org has address 130.226.232.145

Somehow, ntpd (or libc) is caching the result of the lookup where it
previously didn't.

But this doesn't make sense, since neither ntpd nor libc nor
/etc/{nsswitch,ntp,resolv}.conf have changed since it last worked.

For now, I'm going to work around it by explicitly using
[1-3].europe.pool.ntp.org, but I'd really like to know what's going
on...

DES
-- 
Dag-Erling Smørgrav - des_at_des.no