Hello,
I'm trying to set-up a VPN on a vti (ipsec tunnel) interface.
Now, isc-dhcp-servers starts without complaining about an "unsupported interface type".
But it still ignores all requests received on vti0 interface.
My server has 2 interfaces :
ens18:1 : public ip address used to bring up ipsec vpn
DHCP clients requests are relayed from the client network (
192.168.2.0/24) via a DHCP relay (192.168.2.1) to 192.168.155.17 (ip address of dhcp server on ens18 interface)
using tcpdump on vti0 interface, I see DHCP requests incoming :
ip10:25:17.192146 ip: (tos 0x0, ttl 63, id 6882, offset 0, flags [none], proto UDP (17), length 576)
192.168.2.1.67 > 192.168.155.17.67: BOOTP/DHCP, Request from 00:08:5d:47:06:12, length 548, hops 1, xid 0xdba36871, Flags [none]
Gateway-IP 192.168.2.1
Client-Ethernet-Address 00:08:5d:47:06:12
Vendor-rfc1048 Extensions
Magic Cookie 0x63825363
DHCP-Message Option 53, length 1: Discover
Client-ID Option 61, length 7: ether 00:08:5d:47:06:12
Hostname Option 12, length 17: "6737i00085D470612"
Vendor-Class Option 60, length 18: "AastraIPPhone6737i"
Requested-IP Option 50, length 4: 192.168.2.179
MSZ Option 57, length 2: 576
Parameter-Request Option 55, length 13:
Subnet-Mask, Time-Zone, Default-Gateway, Domain-Name-Server
Hostname, Domain-Name, BR, NTP
Vendor-Option, TFTP, Option 132, Option 159
Option 160
server runs like this : /usr/sbin/dhcpd -4 -d -f -cf /etc/dhcp/dhcpd.conf vti0
Here-s the startup output :
# /usr/sbin/dhcpd -4 -f -d -cf /etc/dhcp/dhcpd.conf vti0
Internet Systems Consortium DHCP Server 4.4.2
Copyright 2004-2020 Internet Systems Consortium.
All rights reserved.
For info, please visit
https://www.isc.org/software/dhcp/Config file: /etc/dhcp/dhcpd.conf
Database file: /var/lib/dhcp/dhcpd.leases
PID file: /var/run/dhcpd.pid
Wrote 0 class decls to leases file.
Wrote 0 leases to leases file.
Listening on LPF/vti0//
10.10.0.0/30Sending on LPF/vti0//
10.10.0.0/30Sending on Socket/fallback/fallback-net
Server starting service.
no more logs when an incoming DHCP request arrives on vti0
AM I doing something wrong ?
Regards
Cédric
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