[SOLVED] DHCP | Kea and iSC in parallel on different interfaces - possible?

[imk82]

Hi all,

I tried to use, afterwards a little bit naive it seems, to use ISC and Kea in parallel on different interface. Thought and done, ISC configured for interface 1 (disabled for all others) and same for Kea but with interface 2.

Result: nothing working on interface 2.

After some digging into it I noticed that ISC is listening on all addresses / interfaces + port 67 and Kea was not running at all. Further, after stopping ISC, Kea starts up and listens (correctly) only to the address of interface 2.

For me now the folling questions came up:
1. Which log show that Kea cannot start up / be bound (assumed) to port 67 when ISC is running (system and Kea logs are quiet in that direction)?
2. How can I limit ISC to listen only to the address of interface 1?

See below for details.

Thanks and best regards
Robert

ISC and Kea started up in parallel:

Code Select Expand

USER     COMMAND    PID   FD  PROTO  LOCAL ADDRESS         FOREIGN ADDRESS     
dhcpd    dhcpd      28419 10  udp4   *:67                  *:*


Kea without ISC:

Code Select Expand

USER     COMMAND    PID   FD  PROTO  LOCAL ADDRESS         FOREIGN ADDRESS     
root     kea-dhcp4  97500 14  udp4   172.21.165.1:67       *:*

[franco]

Yes one eternal downside of ISC DHCP is that it's sitting on top of all interfaces blocking the competition.

This was also a problem for the ISC DHCRelay but thankfully neither Kea or the new DHCRelay have that restriction.

All in all, however, the answer is no you cannot for this exact reason.

[imk82]

Hi Franco,

ok, thanks for the confirmation of my guess.

Best regards
Robert