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dnsmasq setting clarification - IPv4 address and strict-order

1. On the Setup tab for my account, under Linked IP it lists these DNS servers:

45.90.28.64

45.90.30.64

But under Setup Guide, if you select Linux (or Routers), for dnsmasq (and stubby, knot, etc.) it lists these DNS servers:

45.90.28.0

45.90.30.0

I went with the .0 servers and it seems to be working okay. But I was wondering, maybe I should be using .64, was I given .64 for load-balancing purposes and the guide for dnsmasq just didn't update?

2. In the Setup Guide for dnsmasq it asks for strict-order and lists 45.90.30.0 before 45.90.28.0 (I don't have IPv6 so I left that out). Is the intent to mainly use 45.90.30.0, and only use 45.90.28.0 if it doesn't respond? dnsmasq unfortunately seems to ignore the order, here is the order they appear in my dnsmasq.conf:

server=45.90.30.0
server=45.90.28.0
strict-order

but here is what the log shows on startup

Dec  9 14:00:51 dnsmasq[19282]: using nameserver 45.90.28.0#53
Dec  9 14:00:51 dnsmasq[19282]: using nameserver 45.90.30.0#53
 

and here are the statistics

Dec  9 21:10:16 dnsmasq[19282]: server 45.90.28.0#53: queries sent 20537, retried or failed 2668
Dec  9 21:10:16 dnsmasq[19282]: server 45.90.30.0#53: queries sent 2854, retried or failed 6

So it's definitely preferring 45.90.28.0. I think I would probably get better performance if it would prefer 45.90.30.0 since my ping there is about half what it is to 45.90.28.0

 

  vultr-sea    27 ms

 anexia-yto   31 ms  (secondary)

  vultr-yto    32 ms

  vultr-chi    55 ms

  zepto-ymq    59 ms

 zepto-xrs    65 ms  (primary)

  vultr-sjc    69 ms

  do-sfo       71 ms

  vultr-lax    72 ms

  anexia-lax   73 ms

  zepto-lax    80 ms
 

Not that the performance is bad or anything. But again I was wondering if I should try to prefer 45.90.30.0 for load-balancing purposes or something.

 

I guess for issue #2 there is probably no fix other than to report it to dnsmasq, or use something else.

2 replies

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    • olivier
    • 3 yrs ago
    • Reported - view

    The non .0 IPs are only useful for the Link IP feature. If you are using DoH or DoT (or even EDNS0 CPE ID with dnsmasq), the .0 IPs should be used. Note that the last byte of the IPv4 does not change anything to the routing or server selection.

    The 3rd byte (28 or 30) defines the primary and secondary server pool. We designed them so they use different providers, different network routes etc. One might give slightly better performance than the other depending on your origin network and location, but in your case, the latency difference is not big, it won't make much difference. The goal is to offer two really different redundant destinations, so if one route would break, the other would likely not.

    If you want to prefer 30, try put it last with strict-order.

    • Jared_Epp
    • 3 yrs ago
    • Reported - view

    Thanks for the quick reply on this and the question I had back on the other forum as well!

    I am using the CPE ID with dnsmasq so I will keep using the .0 IPs.

    I swapped the order in the config file and it is preferring 30 now as well.  Thanks for the suggestion!

Content aside

  • 3 yrs agoLast active
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