On 2019-12-11 10:10:17 +0100 (+0100), Ignazio Cassano wrote: [...]
Dec 11 09:49:06 podto2-osctrl01 dnsmasq-dhcp[70093]: cannot send DHCP/BOOTP option 121: no space left in packet [...]
This error is fairly straightforward. DHCP replies are limited to what you can fit in a single UDP packet and how large of a datagram the client agrees to accept. The number of routes you're trying to include in via option 121 could be the problem (is it a bunch?) but also the other fields and their lengths can also contribute, as can the MTU on that network segment: https://tools.ietf.org/html/rfc2131 According to IETF RFC 2131 you should be able to assume clients will accept a datagram of up to 576 octets in length (which implies your entire options field can use at least 312 octets). Anything over this requires negotiation of a maximum DHCP message size with the client. -- Jeremy Stanley