Comment 11 for bug 1481388

I also noticed the situation can be reproduced at boot if the value of "net.core.rmem_default" is too low.

I reproduced it by only lowering the "net.core.rmem_default = 2000" value with 6 network interface at boot.

ntpd[851]: ntp_io: estimated max descriptors: 1024, initial socket boundary: 16
ntpd[851]: Listen and drop on 0 v4wildcard 0.0.0.0 UDP 123
ntpd[851]: Listen and drop on 1 v6wildcard :: UDP 123
ntpd[851]: Listen normally on 2 eth1 192.168.1.10 UDP 123
ntpd[851]: Listen normally on 3 eth2 192.168.2.10 UDP 123
ntpd[851]: Listen normally on 4 eth3 192.168.3.10 UDP 123
ntpd[851]: Listen normally on 5 eth4 192.168.4.10 UDP 123
ntpd[851]: Listen normally on 6 eth5 192.168.5.10 UDP 123
ntpd[851]: Listen normally on 7 eth6 192.168.6.10 UDP 123
ntpd[851]: peers refreshed
ntpd[851]: Listening on routing socket on fd #24 for interface updates
ntpd[851]: Deferring DNS for 0.ubuntu.pool.ntp.org 1
ntpd[851]: Deferring DNS for 1.ubuntu.pool.ntp.org 1
ntpd[851]: Deferring DNS for 2.ubuntu.pool.ntp.org 1
ntpd[851]: Deferring DNS for 3.ubuntu.pool.ntp.org 1
ntpd[851]: Deferring DNS for ntp.ubuntu.com 1
ntpd[864]: signal_no_reset: signal 17 had flags 4000000
===> ntpd[851]: i/o error on routing socket No buffer space available - disabling <===