dhcpd fails to start on boot with 7.2

[smithgcovert1]

Hi,

Since upgrading to CentOS 7.2, dhpcd fails to start during boot.

It looks like systemd starts it, thinks something has failed, stops it, and then goes through this 10 times, and gives up. There are no errors from dhpcd itself in the /var/log/messages, it looks like all normal dhcpd start stuff -- systemd just says that it failed to start, and does a stop anyway.

I've fixed it / worked around the problem by putting "systemctl start dhpcd" into the rc.local file. This start, after everything else has come up, always works 100%, no problems.

Since the start in rc.local works fine, I know there is no problem with my config files or the the setup itself -- the failure only happens during boot up. And I never had the problem before the upgrade.

Just wondering if anyone else has seen this problem, and has a better solution. I hate starting stuff in rc.local.

Cheers,
Greg

[aks]

Perhaps the "real" failure information is in the jounral (journalctl -b for the last boot or the boot id for a previous boot).

[smithgcovert1]

Here's my output of journalctl -b | grep dhcpd

I didn't see anything really that indicates an error, just that systemd seems to think its died, and continues to restart it.

Guess this isn't happening to anyone else? I set the dhpcd server to only listen to a single interface, incase it was the coming up of my VPN or Docker that caused the problem...

Code: Select all

[root@mighty ~]# journalctl -b | grep dhcpd
Jan 09 00:16:40 mighty.mighty.sytes.net dhcpd[2388]: Internet Systems Consortium DHCP Server 4.2.5
Jan 09 00:16:40 mighty.mighty.sytes.net dhcpd[2388]: Copyright 2004-2013 Internet Systems Consortium.
Jan 09 00:16:40 mighty.mighty.sytes.net dhcpd[2388]: All rights reserved.
Jan 09 00:16:40 mighty.mighty.sytes.net dhcpd[2388]: For info, please visit https://www.isc.org/software/dhcp/
Jan 09 00:16:40 mighty.mighty.sytes.net dhcpd[2388]: Not searching LDAP since ldap-server, ldap-port and ldap-base-dn were not specified in the config file
Jan 09 00:16:40 mighty.mighty.sytes.net dhcpd[2388]: Internet Systems Consortium DHCP Server 4.2.5
Jan 09 00:16:40 mighty.mighty.sytes.net dhcpd[2388]: Copyright 2004-2013 Internet Systems Consortium.
Jan 09 00:16:40 mighty.mighty.sytes.net dhcpd[2388]: All rights reserved.
Jan 09 00:16:40 mighty.mighty.sytes.net dhcpd[2388]: For info, please visit https://www.isc.org/software/dhcp/
Jan 09 00:16:40 mighty.mighty.sytes.net dhcpd[2388]: Wrote 46 leases to leases file.
Jan 09 00:16:42 mighty.mighty.sytes.net dhcpd[2388]: Listening on LPF/enp5s0/10:78:d2:aa:ff:e6/10.0.0.0/24
Jan 09 00:16:42 mighty.mighty.sytes.net dhcpd[2388]: Sending on   LPF/enp5s0/10:78:d2:aa:ff:e6/10.0.0.0/24
Jan 09 00:16:42 mighty.mighty.sytes.net dhcpd[2388]: Sending on   Socket/fallback/fallback-net
Jan 09 00:16:42 mighty.mighty.sytes.net dhcpd[3951]: Internet Systems Consortium DHCP Server 4.2.5
Jan 09 00:16:42 mighty.mighty.sytes.net dhcpd[3951]: Copyright 2004-2013 Internet Systems Consortium.
Jan 09 00:16:42 mighty.mighty.sytes.net dhcpd[3951]: All rights reserved.
Jan 09 00:16:42 mighty.mighty.sytes.net dhcpd[3951]: For info, please visit https://www.isc.org/software/dhcp/
Jan 09 00:16:42 mighty.mighty.sytes.net dhcpd[3951]: Not searching LDAP since ldap-server, ldap-port and ldap-base-dn were not specified in the config file
Jan 09 00:16:42 mighty.mighty.sytes.net dhcpd[3951]: Internet Systems Consortium DHCP Server 4.2.5
Jan 09 00:16:42 mighty.mighty.sytes.net dhcpd[3951]: Copyright 2004-2013 Internet Systems Consortium.
Jan 09 00:16:42 mighty.mighty.sytes.net dhcpd[3951]: All rights reserved.
Jan 09 00:16:42 mighty.mighty.sytes.net dhcpd[3951]: For info, please visit https://www.isc.org/software/dhcp/
Jan 09 00:16:42 mighty.mighty.sytes.net dhcpd[3951]: Wrote 46 leases to leases file.
Jan 09 00:16:43 mighty.mighty.sytes.net dhcpd[3951]: Listening on LPF/enp5s0/10:78:d2:aa:ff:e6/10.0.0.0/24
Jan 09 00:16:43 mighty.mighty.sytes.net dhcpd[3951]: Sending on   LPF/enp5s0/10:78:d2:aa:ff:e6/10.0.0.0/24
Jan 09 00:16:43 mighty.mighty.sytes.net dhcpd[3951]: Sending on   Socket/fallback/fallback-net
Jan 09 00:16:43 mighty.mighty.sytes.net dhcpd[3951]: DHCPDISCOVER from d0:4d:2c:f7:66:db (NP-5Y259H127991) via enp5s0
Jan 09 00:16:43 mighty.mighty.sytes.net dhcpd[3951]: ICMP Echo reply while lease 10.0.0.253 valid.
Jan 09 00:16:43 mighty.mighty.sytes.net dhcpd[3951]: Abandoning IP address 10.0.0.253: pinged before offer
Jan 09 00:16:44 mighty.mighty.sytes.net dhcpd[6481]: Internet Systems Consortium DHCP Server 4.2.5
Jan 09 00:16:44 mighty.mighty.sytes.net dhcpd[6481]: Copyright 2004-2013 Internet Systems Consortium.
Jan 09 00:16:44 mighty.mighty.sytes.net dhcpd[6481]: All rights reserved.
Jan 09 00:16:44 mighty.mighty.sytes.net dhcpd[6481]: For info, please visit https://www.isc.org/software/dhcp/
Jan 09 00:16:44 mighty.mighty.sytes.net dhcpd[6481]: Not searching LDAP since ldap-server, ldap-port and ldap-base-dn were not specified in the config file
Jan 09 00:16:44 mighty.mighty.sytes.net dhcpd[6481]: Internet Systems Consortium DHCP Server 4.2.5
Jan 09 00:16:44 mighty.mighty.sytes.net dhcpd[6481]: Copyright 2004-2013 Internet Systems Consortium.
Jan 09 00:16:44 mighty.mighty.sytes.net dhcpd[6481]: All rights reserved.
Jan 09 00:16:44 mighty.mighty.sytes.net dhcpd[6481]: For info, please visit https://www.isc.org/software/dhcp/
Jan 09 00:16:45 mighty.mighty.sytes.net dhcpd[6481]: Wrote 45 leases to leases file.
Jan 09 00:16:45 mighty.mighty.sytes.net dhcpd[6481]: Listening on LPF/enp5s0/10:78:d2:aa:ff:e6/10.0.0.0/24
Jan 09 00:16:45 mighty.mighty.sytes.net dhcpd[6481]: Sending on   LPF/enp5s0/10:78:d2:aa:ff:e6/10.0.0.0/24
Jan 09 00:16:45 mighty.mighty.sytes.net dhcpd[6481]: Sending on   Socket/fallback/fallback-net
Jan 09 00:16:45 mighty.mighty.sytes.net dhcpd[6630]: Internet Systems Consortium DHCP Server 4.2.5
Jan 09 00:16:45 mighty.mighty.sytes.net dhcpd[6630]: Copyright 2004-2013 Internet Systems Consortium.
Jan 09 00:16:45 mighty.mighty.sytes.net dhcpd[6630]: All rights reserved.
Jan 09 00:16:45 mighty.mighty.sytes.net dhcpd[6630]: For info, please visit https://www.isc.org/software/dhcp/
Jan 09 00:16:45 mighty.mighty.sytes.net dhcpd[6630]: Not searching LDAP since ldap-server, ldap-port and ldap-base-dn were not specified in the config file
Jan 09 00:16:45 mighty.mighty.sytes.net dhcpd[6630]: Internet Systems Consortium DHCP Server 4.2.5
Jan 09 00:16:45 mighty.mighty.sytes.net dhcpd[6630]: Copyright 2004-2013 Internet Systems Consortium.
Jan 09 00:16:45 mighty.mighty.sytes.net dhcpd[6630]: All rights reserved.
Jan 09 00:16:45 mighty.mighty.sytes.net dhcpd[6630]: For info, please visit https://www.isc.org/software/dhcp/
Jan 09 00:16:45 mighty.mighty.sytes.net dhcpd[6630]: Wrote 45 leases to leases file.
Jan 09 00:16:46 mighty.mighty.sytes.net dhcpd[6630]: Listening on LPF/enp5s0/10:78:d2:aa:ff:e6/10.0.0.0/24
Jan 09 00:16:46 mighty.mighty.sytes.net dhcpd[6630]: Sending on   LPF/enp5s0/10:78:d2:aa:ff:e6/10.0.0.0/24
Jan 09 00:16:46 mighty.mighty.sytes.net dhcpd[6630]: Sending on   Socket/fallback/fallback-net
Jan 09 00:16:46 mighty.mighty.sytes.net dhcpd[6950]: Internet Systems Consortium DHCP Server 4.2.5
Jan 09 00:16:46 mighty.mighty.sytes.net dhcpd[6950]: Copyright 2004-2013 Internet Systems Consortium.
Jan 09 00:16:46 mighty.mighty.sytes.net dhcpd[6950]: All rights reserved.
Jan 09 00:16:46 mighty.mighty.sytes.net dhcpd[6950]: For info, please visit https://www.isc.org/software/dhcp/
Jan 09 00:16:46 mighty.mighty.sytes.net dhcpd[6950]: Not searching LDAP since ldap-server, ldap-port and ldap-base-dn were not specified in the config file
Jan 09 00:16:46 mighty.mighty.sytes.net dhcpd[6950]: Internet Systems Consortium DHCP Server 4.2.5
Jan 09 00:16:46 mighty.mighty.sytes.net dhcpd[6950]: Copyright 2004-2013 Internet Systems Consortium.
Jan 09 00:16:46 mighty.mighty.sytes.net dhcpd[6950]: All rights reserved.
Jan 09 00:16:46 mighty.mighty.sytes.net dhcpd[6950]: For info, please visit https://www.isc.org/software/dhcp/
Jan 09 00:16:46 mighty.mighty.sytes.net dhcpd[6950]: Wrote 45 leases to leases file.
Jan 09 00:16:47 mighty.mighty.sytes.net dhcpd[6950]: Listening on LPF/enp5s0/10:78:d2:aa:ff:e6/10.0.0.0/24
Jan 09 00:16:47 mighty.mighty.sytes.net dhcpd[6950]: Sending on   LPF/enp5s0/10:78:d2:aa:ff:e6/10.0.0.0/24
Jan 09 00:16:47 mighty.mighty.sytes.net dhcpd[6950]: Sending on   Socket/fallback/fallback-net
Jan 09 00:16:47 mighty.mighty.sytes.net systemd[1]: start request repeated too quickly for dhcpd.service
Jan 09 00:16:47 mighty.mighty.sytes.net systemd[1]: Unit dhcpd.service entered failed state.
Jan 09 00:16:47 mighty.mighty.sytes.net systemd[1]: dhcpd.service failed.
Jan 09 00:16:47 mighty.mighty.sytes.net nm-dispatcher[2108]: Job for dhcpd.service failed because start of the service was attempted too often. See "systemctl status dhcpd.service" and "journalctl -xe" for details.
Jan 09 00:16:47 mighty.mighty.sytes.net nm-dispatcher[2108]: To force a start use "systemctl reset-failed dhcpd.service" followed by "systemctl start dhcpd.service" again.

[aks]

I see at least one problem:
Jan 09 00:16:43 mighty.mighty.sytes.net dhcpd[3951]: DHCPDISCOVER from d0:4d:2c:f7:66:db (NP-5Y259H127991) via enp5s0
Jan 09 00:16:43 mighty.mighty.sytes.net dhcpd[3951]: ICMP Echo reply while lease 10.0.0.253 valid.
Jan 09 00:16:43 mighty.mighty.sytes.net dhcpd[3951]: Abandoning IP address 10.0.0.253: pinged before offer

Your DHCP server is "handing" out addresses that already exist on the network. This is not normally a problem, in that the DHCP server should just try another address (although that never been the way you use DHCP). I suspect systemctl "sees" this signal and assumes the DHCP server is failing and then restarts it. Stop doing that!

As suggested, you can also try journalctl -xe to see if there's anything else there.