[Dnsmasq-discuss] dhcp-host=hostnameonly does not work

[Maulis Adam]

Hello,

I like to configure my dhcp server with as little redundacy as possible. 
But it looks like the IP address needs to be written both of /etc/hosts 
and /etc/dnsmasq.conf

The client machines are in the /etc/hosts for example:

192.168.64.200 cntemplate.hpc

The non-default dnsmasq config options are:

no-resolv
server=192.168.5.251
expand-hosts
domain=hpc

Case 1:
dhcp-range=192.168.64.0,static
dhcp-host=cntemplate

Does not work, syslog said:
May 19 15:53:47 gw00 dnsmasq-dhcp[4912]: DHCPDISCOVER(vlan164) 02:00:00:00:00:65 no address available

Case 2:
dhcp-range=192.168.64.0,static
dhcp-host=cntemplate,192.168.64.200

Working, but needed a duplicate entry both of /etc/hosts and /etc/dnsmasq.conf

Case 3:
dhcp-range=192.168.64.100,192.168.64.250
dhcp-host=cntemplate,192.168.64.200

Working, but needed a duplicate entry both of /etc/hosts and /etc/dnsmasq.conf

Case 4:
dhcp-range=192.168.64.100,192.168.64.250
dhcp-host=cntemplate

Does not work, syslog said:
May 19 16:15:04 gw00 dnsmasq-dhcp[5282]: not giving name cntemplate.hpc to the DHCP lease of 192.168.64.215 because the name exists in /etc/hosts with address 192.168.64.200





The client's DHCP requests (tcpdump)

02:00:00:00:00:65 > ff:ff:ff:ff:ff:ff, ethertype 802.1Q (0x8100), length 346: vlan 164, p 0, ethertype IPv4 (0x0800), (tos 0x10, ttl 128, id 0, offset 0, flags [none], proto UDP (17), length 328)
     0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request from 02:00:00:00:00:65, length 300, xid 0x619d4060, Flags [none]
           Client-Ethernet-Address 02:00:00:00:00:65
           Vendor-rfc1048 Extensions
             Magic Cookie 0x63825363
             DHCP-Message (53), length 1: Discover
             Hostname (12), length 10: "cntemplate"
             Parameter-Request (55), length 13:
               Subnet-Mask (1), BR (28), Time-Zone (2), Default-Gateway (3)
               Domain-Name (15), Domain-Name-Server (6), Unknown (119), Hostname (12)
               Netbios-Name-Server (44), Netbios-Scope (47), MTU (26), Classless-Static-Route (121)
               NTP (42)

Server's config:

ip addr show vlan164
6: vlan164 at ens5: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
     link/ether 52:54:00:12:34:58 brd ff:ff:ff:ff:ff:ff
     inet 192.168.64.254/24 brd 192.168.64.255 scope global vlan164
        valid_lft forever preferred_lft forever
     inet6 fe80::5054:ff:fe12:3458/64 scope link
        valid_lft forever preferred_lft forever

cat /etc/debian_version
10.12

uname -a
Linux gw00 4.19.0-11-amd64 #1 SMP Debian 4.19.146-1 (2020-09-17) x86_64 GNU/Linux

dpkg -l dnsmasq
ii  dnsmasq        2.80-1+deb10u1 all          Small caching DNS proxy and DHCP/TFTP server

I would be very happy with any advice

Adam Maulis