[Kea-users] Kea-DHCP4 exiting right after start

[Doug Freed]

On 3/13/26 12:47, Alessandro Vesely wrote:
> Hi,
> 
> when the server boots, it starts DNS in this order:
> 
> ...
> lrwxrwxrwx 1 root root 19 Jun 28  2019 S03mynetwork -> ../init.d/mynetwork
> lrwxrwxrwx 1 root root 19 Jul 10  2020 S03rmnologin -> ../init.d/rmnologin
> lrwxrwxrwx 1 root root 26 Oct 18  2021 S03rng-tools-debian -> ../init.d/ 
> rng-tools-debian
> lrwxrwxrwx 1 root root 17 Nov  7 12:59 S04elogind -> ../init.d/elogind
> lrwxrwxrwx 1 root root 26 Nov  7 12:59 S04kea-dhcp4-server -> ../init.d/ 
> kea-dhcp4-server
> lrwxrwxrwx 1 root root 30 Nov  7 12:59 S04kea-dhcp-ddns-server -> ../ 
> init.d/kea-dhcp-ddns-server
> lrwxrwxrwx 1 root root 15 Nov  7 12:59 S04named -> ../init.d/named
> ...
> 
> However, upon login I find no DHCP4.  The log says so:
> 
> Mar 13 17:48:43 INFO  DHCP4_CONFIG_COMPLETE DHCPv4 server has completed 
> configuration: added IPv4 subnets: 1; DDNS: enabled
> Mar 13 17:48:43 INFO  DHCPSRV_MEMFILE_DB opening memory file lease 
> database: name=/var/lib/kea/dhcp4.csv persist=true type=memfile universe=4
> Mar 13 17:48:43 INFO  DHCPSRV_MEMFILE_LEASE_FILE_LOAD loading leases 
> from file /var/lib/kea/dhcp4.csv.2
> Mar 13 17:48:43 INFO  DHCPSRV_MEMFILE_LEASE_FILE_LOAD loading leases 
> from file /var/lib/kea/dhcp4.csv
> Mar 13 17:48:43 INFO  DHCPSRV_MEMFILE_EXTRACT_EXTENDED_INFO4 extracting 
> extended info saw 8 leases, extended info sanity checks modified 0 / 
> updated 0 leases and 0 leases have relay or remote id
> Mar 13 17:48:43 INFO  DHCPSRV_MEMFILE_LFC_SETUP setting up the Lease 
> File Cleanup interval to 3600 sec
> Mar 13 17:48:43 INFO  DHCPSRV_DHCP_DDNS_SENDER_STARTED NameChangeRequest 
> sender has been started: enable_updates: yes, server-ip: 127.0.0.1, 
> server-port: 53001, sender-ip: 0.0.0.0, sender-port: 0, max-queue-size: 
> 1024, ncr-protocol: UDP, ncr-format: JSON
> Mar 13 17:48:43 WARN  DHCPSRV_OPEN_SOCKET_FAIL failed to open socket: 
> the interface eth2r is not running
> Mar 13 17:48:43 INFO  DHCP4_OPEN_SOCKETS_FAILED maximum number of open 
> service sockets attempts: 0, has been exhausted without success
> Mar 13 17:48:43 WARN  DHCPSRV_NO_SOCKETS_OPEN no interface configured to 
> listen to DHCP traffic
> Mar 13 17:48:43 INFO  DHCPSRV_CFGMGR_USE_ALLOCATOR using the iterative 
> allocator for V4 leases in subnet 172.25.197.0/24
> Mar 13 17:48:43 WARN  DHCP4_MULTI_THREADING_INFO enabled: yes, number of 
> threads: 8, queue size: 64
> Mar 13 17:48:43 INFO  DHCP4_STARTED Kea DHCPv4 server version 2.6.3 started
> Mar 13 17:48:43 INFO  DHCP4_SHUTDOWN server shutdown
> 
> 
> S03mynetwork contains a line saying `ip link set eth2r up`.  Indeed, 
> when S04named came up, it logged:
> 
> ...
> Mar 13 17:48:43 30 north named[2073]: listening on IPv4 interface eth2r, 
> 172.25.197.1#53
> Mar 13 17:48:43 30 north named[2073]: listening on IPv6 interface eth2r, 
> 2a02:29e1:500:6c22::1#53
> ...
> 
> Should I change the init order?  Put a pause?  What else?
> 
> TIA for any hint
> Best
> Ale

"The interface eth2r is not running" means the interface does not have 
the "RUNNING" flag, which generally indicates whether the interface is 
actually operational and capable of being used for traffic.  Your 
network script should wait until /sys/class/net/eth2r/operstate contains 
"up" before finishing to ensure that everything is operational. 
Typically this happens rather quickly, but if something like 802.1x is 
involved, it can be a non-zero amount of time waiting for 802.1x to 
complete.  You may want to reorder operations if there are multiple 
interfaces so that 'ip link set eth2r up' is run as early as possible, 
as well any 802.1x auth, so it has time to get the RUNNING flag while 
other operations are being performed before the script completes, so it 
can spend less time waiting for operstate to change.

-Doug