Question

[Leslie Rhorer]

On 6/2/2022 11:15 PM, Glenn Satchell wrote:
> Hi Leslie,
>
> You've got "split 0" in the failover section - this causes dhcpd to 
> prefer one of the servers for all renewals, so this might be a reason 
> only one server is logging any renewals. "split 128" does a 50-50 
> balance between the servers and is the more common setting.


     OK.  I updated the value on both, but now there seems to be some 
more issues on the secondary:

Jun  2 23:42:28 Backup dhcpd[70596]: Internet Systems Consortium DHCP 
Server 4.4.1
Jun  2 23:42:28 Backup dhcpd[70596]: Copyright 2004-2018 Internet 
Systems Consortium.
Jun  2 23:42:28 Backup dhcpd[70596]: All rights reserved.
Jun  2 23:42:28 Backup dhcpd[70596]: For info, please visit 
https://www.isc.org/software/dhcp/
Jun  2 23:42:28 Backup dhcpd[70602]: Internet Systems Consortium DHCP 
Server 4.4.1
Jun  2 23:42:28 Backup dhcpd[70602]: Copyright 2004-2018 Internet 
Systems Consortium.
Jun  2 23:42:28 Backup dhcpd[70602]: All rights reserved.
Jun  2 23:42:28 Backup dhcpd[70602]: For info, please visit 
https://www.isc.org/software/dhcp/
Jun  2 23:42:28 Backup dhcpd[70602]: Wrote 0 deleted host decls to 
leases file.
Jun  2 23:42:28 Backup dhcpd[70602]: Wrote 0 new dynamic host decls to 
leases file.
Jun  2 23:42:28 Backup dhcpd[70602]: Wrote 0 leases to leases file.
Jun  2 23:42:28 Backup dhcpd[70602]: failover peer dhcp-failover: I move 
from recover to startup
Jun  2 23:42:28 Backup dhcpd[70602]: Server starting service.
Jun  2 23:42:28 Backup dhcpd[70602]: Failover CONNECTACK from 
dhcp-failover: already connected
Jun  2 23:42:28 Backup dhcpd[70602]: failover peer dhcp-failover: peer 
moves from unknown-state to recover
Jun  2 23:42:28 Backup dhcpd[70602]: failover peer dhcp-failover: 
requesting full update from peer
Jun  2 23:42:28 Backup dhcpd[70602]: failover peer dhcp-failover: I move 
from startup to recover
Jun  2 23:42:28 Backup dhcpd[70602]: dhcp_failover_put_message: 
something went wrong.
Jun  2 23:42:28 Backup dhcpd[70602]: peer dhcp-failover: disconnected
Jun  2 23:42:33 Backup dhcpd[70602]: Failover CONNECTACK from 
dhcp-failover: already connected
Jun  2 23:42:33 Backup dhcpd[70602]: failover peer dhcp-failover: peer 
moves from recover to recover
Jun  2 23:42:33 Backup dhcpd[70602]: failover peer dhcp-failover: 
requesting full update from peer
Jun  2 23:42:33 Backup dhcpd[70602]: dhcp_failover_put_message: 
something went wrong.
Jun  2 23:42:33 Backup dhcpd[70602]: peer dhcp-failover: disconnected
Jun  2 23:42:33 Backup dhcpd[70602]: Failed to send update request all 
message to dhcp-failover: socket is not connected
Jun  2 23:42:38 Backup dhcpd[70602]: Failover CONNECTACK from 
dhcp-failover: already connected
Jun  2 23:42:38 Backup dhcpd[70602]: failover peer dhcp-failover: peer 
moves from recover to recover
Jun  2 23:42:38 Backup dhcpd[70602]: failover peer dhcp-failover: 
requesting full update from peer
Jun  2 23:42:38 Backup dhcpd[70602]: dhcp_failover_put_message: 
something went wrong.
Jun  2 23:42:38 Backup dhcpd[70602]: peer dhcp-failover: disconnected
Jun  2 23:42:38 Backup dhcpd[70602]: Failed to send update request all 
message to dhcp-failover: socket is not connected
Jun  2 23:42:38 Backup dhcpd[70602]: peer dhcp-failover: disconnected
Jun  2 23:42:43 Backup dhcpd[70602]: peer dhcp-failover: disconnected
Jun  2 23:42:43 Backup dhcpd[70602]: Failover CONNECTACK from 
dhcp-failover: already connected
Jun  2 23:42:43 Backup dhcpd[70602]: failover peer dhcp-failover: peer 
moves from recover to recover
Jun  2 23:42:43 Backup dhcpd[70602]: failover peer dhcp-failover: 
requesting full update from peer
Jun  2 23:42:43 Backup dhcpd[70602]: dhcp_failover_put_message: 
something went wrong.
Jun  2 23:42:43 Backup dhcpd[70602]: peer dhcp-failover: disconnected
Jun  2 23:42:43 Backup dhcpd[70602]: Failed to send update request all 
message to dhcp-failover: socket is not connected
Jun  2 23:42:48 Backup dhcpd[70602]: Failover CONNECTACK from 
dhcp-failover: already connected
Jun  2 23:42:48 Backup dhcpd[70602]: failover peer dhcp-failover: peer 
moves from recover to recover
Jun  2 23:42:48 Backup dhcpd[70602]: failover peer dhcp-failover: 
requesting full update from peer
Jun  2 23:42:48 Backup dhcpd[70602]: dhcp_failover_put_message: 
something went wrong.
Jun  2 23:42:48 Backup dhcpd[70602]: peer dhcp-failover: disconnected
Jun  2 23:42:48 Backup dhcpd[70602]: Failed to send update request all 
message to dhcp-failover: socket is not connected
Jun  2 23:42:48 Backup dhcpd[70602]: peer dhcp-failover: disconnected
Jun  2 23:48:26 Backup dhcpd[70654]: Internet Systems Consortium DHCP 
Server 4.4.1
Jun  2 23:48:26 Backup dhcpd[70654]: Copyright 2004-2018 Internet 
Systems Consortium.
Jun  2 23:48:26 Backup dhcpd[70654]: All rights reserved.
Jun  2 23:48:26 Backup dhcpd[70654]: For info, please visit 
https://www.isc.org/software/dhcp/
Jun  2 23:50:16 Backup dhcpd[70685]: Internet Systems Consortium DHCP 
Server 4.4.1
Jun  2 23:50:16 Backup dhcpd[70685]: Copyright 2004-2018 Internet 
Systems Consortium.
Jun  2 23:50:16 Backup dhcpd[70685]: All rights reserved.
Jun  2 23:50:16 Backup dhcpd[70685]: For info, please visit 
https://www.isc.org/software/dhcp/
Jun  2 23:50:16 Backup dhcpd[70691]: Internet Systems Consortium DHCP 
Server 4.4.1
Jun  2 23:50:16 Backup dhcpd[70691]: Copyright 2004-2018 Internet 
Systems Consortium.
Jun  2 23:50:16 Backup dhcpd[70691]: All rights reserved.
Jun  2 23:50:16 Backup dhcpd[70691]: For info, please visit 
https://www.isc.org/software/dhcp/
Jun  2 23:50:16 Backup dhcpd[70691]: Wrote 0 deleted host decls to 
leases file.
Jun  2 23:50:16 Backup dhcpd[70691]: Wrote 0 new dynamic host decls to 
leases file.
Jun  2 23:50:16 Backup dhcpd[70691]: Wrote 0 leases to leases file.
Jun  2 23:50:16 Backup dhcpd[70691]: failover peer dhcp-failover: I move 
from recover to startup
Jun  2 23:50:16 Backup dhcpd[70691]: Server starting service.
Jun  2 23:50:16 Backup dhcpd[70691]: Failover CONNECTACK from 
dhcp-failover: already connected
Jun  2 23:50:16 Backup dhcpd[70691]: failover peer dhcp-failover: I move 
from startup to recover
Jun  2 23:50:16 Backup dhcpd[70691]: dhcp_failover_put_message: 
something went wrong.
Jun  2 23:50:16 Backup dhcpd[70691]: peer dhcp-failover: disconnected
Jun  2 23:50:21 Backup dhcpd[70691]: Failover CONNECTACK from 
dhcp-failover: already connected
Jun  2 23:50:21 Backup dhcpd[70691]: failover peer dhcp-failover: peer 
moves from recover to recover
Jun  2 23:50:21 Backup dhcpd[70691]: failover peer dhcp-failover: 
requesting full update from peer
Jun  2 23:50:21 Backup dhcpd[70691]: dhcp_failover_put_message: 
something went wrong.
Jun  2 23:50:21 Backup dhcpd[70691]: peer dhcp-failover: disconnected
Jun  2 23:50:21 Backup dhcpd[70691]: Failed to send update request all 
message to dhcp-failover: socket is not connected
Jun  2 23:50:26 Backup dhcpd[70691]: Failover CONNECTACK from 
dhcp-failover: already connected
Jun  2 23:50:26 Backup dhcpd[70691]: failover peer dhcp-failover: peer 
moves from recover to recover
Jun  2 23:50:26 Backup dhcpd[70691]: failover peer dhcp-failover: 
requesting full update from peer
Jun  2 23:50:26 Backup dhcpd[70691]: dhcp_failover_put_message: 
something went wrong.
Jun  2 23:50:26 Backup dhcpd[70691]: peer dhcp-failover: disconnected
Jun  2 23:50:26 Backup dhcpd[70691]: Failed to send update request all 
message to dhcp-failover: socket is not connected

>
> "not responding (recovering)" sounds like the failover protocol hasn't 
> synced between the servers, so it won't respond to any requests while 
> it's in that state to prevent both dhcpd servers handing out 
> conflicting responses, eg both hand out the same IP to different 
> clients. dhcpd will log messages to syslog when failover states change.
>
> You could use tcpdump or wireshark to look and see if there is any 
> traffic on tcp port 647 between the servers. Also the dhcpd.conf man 
> page in the section titled FAILOVER STARTUP goes through the steps and 
> may help debug what's going on.
>
> I think you might have already done this, bu check there is no local 
> firewall rules on the server blocking failover traffic between those 
> ports.


     There are no firewalls.

>
> dhcpd.leases is the current lease file, you can run tail -f to see 
> updates being appended. Every hour it renames this to dhcpd.leases~ 
> and writes out a new dhcpd.leases from the in-memory copy of the data. 
> dhcpd.leases is only ever appended to, so you can have multiple 
> entries for the same IP address - the last one is the active state. 
> When the file gets re-written it removes all the duplicate records.

     OK, but neither server is writing any leases to the leases files.  
They talk plenty about their peer status, but nothing about any leases, 
despite the fact the primary, at least, is issuing leases, and the 
secondary does as well if the primary is offline.