[Dnsmasq-discuss] Long nslookup times

[Donald Muller]

Hello all,

I have Microsoft DNS and DHCP running on a Windows 2012 R2 server. The processor is a 4 core 4 thread i5-4440 running at 3.1GHz with 16GB of memory. I am in the process of retiring this server and moving everything over to a QNAP NAS which runs Linux. The NAS is running a 4 core 8 thread i7-7700 running at 3.6GHz with 40GB of memory. The Linux NAS is faster and has more threads and memory. I have installed dnsmasq on the NAS and DNS and DHCP are working. However during testing I ran into a strange issue.

Running an nslookup on the NAS using the DNS on the NAS takes a lot longer than it does using the DNS running on the 2012 server.

Using Microsoft DNS server

[~] # time nslookup www.microsoft.com 192.168.22.200
Server:    192.168.22.200
Address 1: 192.168.22.200 djmfs1.djmuller.com

Name:      www.microsoft.com
Address 1: 172.229.210.230 a172-229-210-230.deploy.static.akamaitechnologies.com
Address 2: 2001:428:4404:18f::356e
Address 3: 2001:428:4404:192::356e

real    0m0.103s
user    0m0.001s
sys     0m0.000s

Using dnsmasq

[~] # time nslookup www.microsoft.com 192.168.22.220
Server:    192.168.22.220
Address 1: 192.168.22.220 DJMFS2

Name:      www.microsoft.com
Address 1: 172.229.210.230 a172-229-210-230.deploy.static.akamaitechnologies.com
Address 2: 2001:428:4404:192::356e
Address 3: 2001:428:4404:18f::356e

real    0m40.057s
user    0m0.000s
sys     0m0.001s

As you can see dnsmasq took a lot longer. Both DNS servers are set up to forward requests to my router (192.168.22.252) which then forwards them on the my ISP DNS servers. The router is NOT running a DNS server. Some queries run faster on the NAS. Others, like www.micorsoft.com run slower. Here is my dnsmasq setup.

Main dnsmasq config file

user=xxxxx
group=yyyyyyy
log-facility=/share/CACHEDEV1_DATA/UserData/Logs/DNSMasq/dnsmasq.log
log-async=25
bind-dynamic
conf-file=/share/CACHEDEV1_DATA/UserData/Configs/DNSMasq/dnsmasq-dns.conf                                                       # DNS configuration information
conf-file=/share/CACHEDEV1_DATA/UserData/Configs/DNSMasq/dnsmasq-dhcp.conf                                                     # DHCP configuration information

dnsmasq-dns.conf file

domain-needed
domain=djmuller.com
no-hosts
addn-hosts=/share/CACHEDEV1_DATA/UserData/Configs/DNSMasq/dnsmasq-hosts.conf
expand-hosts
#log-queries
local-service
bogus-priv
filterwin2k
resolv-file=/share/CACHEDEV1_DATA/UserData/Configs/DNSMasq/dnsmasq-resolv.conf
stop-dns-rebind
rebind-localhost-ok
no-poll
clear-on-reload
domain-needed
mx-host=djmuller.com,djmuller.com,50
mx-target=mail.djmuller.com
cache-size=1000
conf-file=/share/CACHEDEV1_DATA/UserData/Configs/DNSMasq/dnsmasq-adservers.conf                                           # List of servers that will return no-domain
rebind-domain-ok=/plex.direct/

Is there a setting that needs to be changed/added/removed? What additional information do you need?

Thanks
Don
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/attachments/20180130/0aaec74e/attachment.html>