[Dnsmasq-discuss] multiple upstream servers

[S Irlapati]

Here are a few experiments that have been done.

Config file:

port=53
bogus-priv
no-resolv
local=/localnet/
user=dnsmasq
group=dnsmasq
interface=enp5s0
listen-address=127.0.0.1,192.168.13.1
expand-hosts
domain=irlanet.org
dhcp-range=192.168.13.224,192.168.13.255,2h
dhcp-authoritative
cache-size=0
cname=win-sji,MOEDW1CKH5
log-queries
log-dhcp

dhcp-host=40:16:7e:63:60:d1,Salem,set:red,192.168.13.102

dhcp-option=tag:red,option:dns-server,10.88.13.3
dhcp-option=tag:green,option:dns-server,10.88.13.4
dhcp-option=option:dns-server,10.88.13.4
server=10.88.13.4#53

 From the host Salem when forcing a quiery:

@salem 558]>curl ident.me
154.21.57.55

 From dnsmasq server log files

Jul 29 18:17:56 xroads dnsmasq[3822653]: query[A] ident.me from 
192.168.13.102
Jul 29 18:17:56 xroads dnsmasq[3822653]: forwarded ident.me to 10.88.13.4
Jul 29 18:17:56 xroads dnsmasq[3822653]: query[AAAA] ident.me from 
192.168.13.102
Jul 29 18:17:56 xroads dnsmasq[3822653]: forwarded ident.me to 10.88.13.4
Jul 29 18:17:56 xroads dnsmasq[3822653]: reply ident.me is 176.58.123.25
Jul 29 18:17:56 xroads dnsmasq[3822653]: reply ident.me is 
2a01:7e00::f03c:91ff:fe70:2b9d

The goal is to make queries from Salem to be forwared to 10.88.13.4

 From here only the serveer lines will be changed.

dhcp-option=tag:red,option:dns-server,10.88.13.3
dhcp-option=tag:green,option:dns-server,10.88.13.4
dhcp-option=option:dns-server,10.88.13.4
# server=10.88.13.4#53

Query from Salem results:

@salem 558]>curl ident.me
curl: (6) Could not resolve host: ident.me

Dnsmasq log file output:

Jul 29 18:20:57 xroads dnsmasq[4042096]: query[A] ident.me from 
192.168.13.102
Jul 29 18:20:57 xroads dnsmasq[4042096]: query[AAAA] ident.me from 
192.168.13.102
Jul 29 18:20:57 xroads dnsmasq[4042096]: query[A] ident.me from 
192.168.13.102
Jul 29 18:20:57 xroads dnsmasq[4042096]: query[AAAA] ident.me from 
192.168.13.102
Jul 29 18:20:57 xroads dnsmasq[4042096]: query[A] ident.me.irlanet.org 
from 192.168.13.102
Jul 29 18:20:57 xroads dnsmasq[4042096]: query[AAAA] 
ident.me.irlanet.org from 192.168.13.102
Jul 29 18:20:57 xroads dnsmasq[4042096]: query[A] ident.me.irlanet.org 
from 192.168.13.102
Jul 29 18:20:57 xroads dnsmasq[4042096]: query[AAAA] 
ident.me.irlanet.org from 192.168.13.102

It looks like dnsmasq does not know where to forward the requests.

Changing the servers again:

dhcp-option=tag:red,option:dns-server,10.88.13.3
dhcp-option=tag:green,option:dns-server,10.88.13.4
dhcp-option=option:dns-server,10.88.13.4
server=10.88.13.3#53

Querying from Salem:

@salem 558]>curl ident.me
154.21.57.55

Dnsmasq log file:

Jul 29 18:23:36 xroads dnsmasq[4105784]: query[A] ident.me from 
192.168.13.102
Jul 29 18:23:36 xroads dnsmasq[4105784]: forwarded ident.me to 10.88.13.3
Jul 29 18:23:36 xroads dnsmasq[4105784]: query[AAAA] ident.me from 
192.168.13.102
Jul 29 18:23:36 xroads dnsmasq[4105784]: forwarded ident.me to 10.88.13.3
Jul 29 18:23:36 xroads dnsmasq[4105784]: reply ident.me is 176.58.123.25
Jul 29 18:23:36 xroads dnsmasq[4105784]: reply ident.me is 
2a01:7e00::f03c:91ff:fe70:2b9d

 From the above experiments it looks like dhcp-option is completely 
ignored.

Does anyone see a problem with the config?