Troubles with DNS (potentially more?)

[Semper]

Going to keep it as short as I can. If you need more info, ask away, I'll provide it!

The issue:
Several times an hour (for the most part), over the last 48 hours, my WAN network will go down. There doesn't appear to be any regular pattern to the downtime, they can happen seconds, minutes, or hours apart. So far as I'm able to tell, my LAN network is also down during this time, as i'm unable to access either the modem or router configuration addresses (would there be a way to verifiable test this, given the random and unpredictable time frame that the issue presents as?). The outage will be for an incredibly short period of time, some as quick as 1-2 seconds, the average being 10-15 seconds. Running network diagnostics during this time always produces a result of either "The DNS server isn't responding" (very common), or a "Your computer appears to be correctly configured, but the device or resource (DNS server) is not responding" (uncommon)

The hardware:
Netgear R6400 running DD-WRT  (v3.0-r37015m) (so far as I'm able to find, the most up-to-date version) Been running the custom firmware for a little over a month.
Netgear CM600, stock firmware (V1.01.14) (so far as I'm able to tell, the most recent version) installed roughly a week ago, replacing an SB6121. The SB6121 was regularly producing T3, T4 and T6 timeout errors. The CM600 does not appear to have fully resolved the timeout errors as two T6 errors have occurred since the installation
(connection signal readouts if you'd like to see them)

Spoiler

Startup Procedure

Procedure Status Comment Acquire Downstream Channel 705000000 Hz Locked Connectivity State OK Operational Boot State OK Operational Security Enable BPI+ IP Provisioning Mode Override MDD IPv6 only

Downstream Bonded Channels=-1>

Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables 1 Locked QAM256 31 705000000 Hz 0.2 dBmV 40.5 dB 0 0 2 Locked QAM256 3 531000000 Hz 0.1 dBmV 41.6 dB 0 0 3 Locked QAM256 4 537000000 Hz 0.1 dBmV 41.6 dB 0 0 4 Locked QAM256 5 543000000 Hz 0.1 dBmV 41.6 dB 0 0 5 Locked QAM256 7 555000000 Hz 0.3 dBmV 41.5 dB 0 0 6 Locked QAM256 8 561000000 Hz 0.3 dBmV 41.5 dB 0 0 7 Locked QAM256 9 567000000 Hz 0.4 dBmV 41.6 dB 0 0 8 Locked QAM256 10 573000000 Hz 0.3 dBmV 41.6 dB 0 0 9 Locked QAM256 11 579000000 Hz 0.4 dBmV 41.6 dB 0 0 10 Locked QAM256 12 585000000 Hz 0.3 dBmV 41.5 dB 0 0 11 Locked QAM256 13 591000000 Hz 0.3 dBmV 41.5 dB 0 0 12 Locked QAM256 14 597000000 Hz 0.2 dBmV 41.4 dB 0 0 13 Locked QAM256 15 603000000 Hz 0.3 dBmV 41.4 dB 0 0 14 Locked QAM256 16 609000000 Hz 0.1 dBmV 41.2 dB 0 0 15 Locked QAM256 18 621000000 Hz 0.1 dBmV 41.1 dB 0 0 16 Locked QAM256 19 627000000 Hz 0.2 dBmV 41.2 dB 0 0 17 Locked QAM256 21 639000000 Hz -0.3 dBmV 42.3 dB 0 0 18 Locked QAM256 22 645000000 Hz -0.2 dBmV 42.2 dB 0 0 19 Locked QAM256 24 657000000 Hz -0.5 dBmV 42.0 dB 0 0 20 Locked QAM256 25 663000000 Hz -0.6 dBmV 41.9 dB 0 0 21 Locked QAM256 26 669000000 Hz -0.6 dBmV 41.9 dB 0 0 22 Locked QAM256 28 681000000 Hz -0.4 dBmV 41.9 dB 0 0 23 Locked QAM256 29 687000000 Hz -0.5 dBmV 41.8 dB 0 0 24 Locked QAM256 30 699000000 Hz -0.2 dBmV 41.9 dB 0 0

Upstream Bonded Channels=-1>

Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power 1 Locked ATDMA 65 5120 Ksym/sec 17800000 Hz 46.5 dBmV 2 Locked ATDMA 66 5120 Ksym/sec 24200000 Hz 46.8 dBmV 3 Locked ATDMA 67 5120 Ksym/sec 30600000 Hz 47.3 dBmV 4 Locked ATDMA 68 5120 Ksym/sec 37000000 Hz 47.3 dBmV 5 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV

Current System Time: Tue Jun 25 06:25:22 2019

          Five wireless clients

             3x iPhones (7+, 8, 8+)
             1x Google Home Mini
             1x TP-Link Smart Plug

          One wired client (my PC)

The configuration (as it relates to DNS, ask if you need to know more):
Attempted using (ipv4 and ipv6 for the following):
ISP (Spectrum) provided default DNS
OpenDNS
Google Public DNS
Cloudflare DNS

All produced the same result, sporadic, unpredictable DNS errors (timeouts?)


Networking isn't something that I have a firm grasp of. I'd go so far as to state that it's my weak point when it comes to technology. I've exhausted everything that I can come up with, even using Google support. If anyone is able to lend a hand in resolving these issues, it'd be genuinely appreciated!

[narrdarr]

try

disabling ipv6

set static ip addresses for devices( or at least your wired pc)

lets use dns 8.8.8.8 and 8.8.4.4 for secondary (google dns)

set on pc and in router

 

 

[Semper]

1 minute ago, narrdarr said:

try

disabling ipv6

set static ip addresses for devices( or at least your wired pc)

lets use dns 8.8.8.8 and 8.8.4.4 for secondary (google dns)

set on pc and in router

 

 

The issues persist even with IPv6 disabled, apologies, I probably should have made that more clear. All four were tried with base IPv4 (v6 being completely disabled on my router), with only IPv6 (meaning my default v4 DNS would be the fallback), and with both v4 and v6.

The wired client already uses a static IP (.12), the wireless clients (at least the iPhones) don't have static addresses as they had connectivity issues when trying to rejoin the network for some reason.

For the sake of troubleshooting with your post, v6 is disabled again, and i'm running google's DNS both on the router and through Windows network manager, it'll take me some time (unknown, for what I'd hope are obvious reasons :P) to verify that the issue still persists

[narrdarr]

static ip .12 is set on pc, but is the ip address reserved or set for the pc.

 

if other device are having trouble connecting. the issue maybe in your DHCP settings

you could try reducing the dhcp lease time in the router

sometimes need to reset router

try connecting another device

 

 

[Semper]

24 minutes ago, narrdarr said:

static ip .12 is set on pc, but is the ip address reserved or set for the pc.

 

if other device are having trouble connecting. the issue maybe in your DHCP settings

you could try reducing the dhcp lease time in the router

sometimes need to reset router

try connecting another device

 

 

 

I believe it's reserved. The router interface has the MAC set to static, and the DHCP clients list has it as static as well
https://imgur.com/a/qwsZ57N

Without assigning static IP's to the wireless clients, the connectivity issues aren't present, it's only when attempting to make them static. When initially established, the static connections are fine, until which point that the devices leave the network (I.E. leaving the house and returning), Some of the time they would reconnect, some of the time, they wouldn't.

DHCP lease is set for 1440 minutes, 24 hours
DHCP settings:
https://imgur.com/a/NNFeYqB

 

I don't have any more devices to add to my network, everything in use is already attached.

The DNS issues also still persist with ipv6 disabled and on Google's DNS, when attempting to upload one of the screenshots above, the network went down.

[narrdarr]

ipv6 can be turned back on

 

Dhcp setting look fine

i usually use larger max dhcp users, but that shouldn't matter

 

this starting to look like an issue on the isp side.

 

as for you wireless device were you trying to set static ips inside or outside the dhcp range?

[narrdarr]

next time you loose connection can you try connection to https://172.217.0.46 (google.com) by ip address through the address bar in your web browser

 

you can confirm ip address using

cmd

nslookup google.com

 

 

 

[Semper]

8 minutes ago, narrdarr said:

ipv6 can be turned back on

 

Dhcp setting look fine

i usually use larger max dhcp users, but that shouldn't matter

 

this starting to look like an issue on the isp side.

 

as for you wireless device were you trying to set static ips inside or outside the dhcp range?

50 is default for DD-WRT, I figured so far as i'm only using a max of seven clients on my current network, it wasn't much of an issue to leave it as such, it's only a household of three people

I"ll get in contact with Spectrum in that case, see if they're having known issues. It just doesn't strike me as an ISP issue seeing as i'm not actually using their DNS, but then again, networking isn't my strong point, so I may genuinely not be correlating things here.

When attempting to static IP the wireless clients, I was using IP's outside the range, .12 - .16

When it comes to accessing a website through a domain, is it processed differently when accessing it directly by IP? My understanding is it's functionally the same

[narrdarr]

dns is like contact list

if we use a phone for example:

you say call john doe. the phone translate john doe to a number like (555)555-5555 then calls

the translation part is what the dns handles but for the internet aka you want google.com( a domain name) . when  you press enter to call for google.com dns looks ups the ip address then calls for the ip. i was wonder if you have a problem when calling for the ip directly.

 

but i'm leaning toward an isp issue as your isp dns, google dns, and open dns should all be stable, but all are giving trouble.

_________

connective of the wireless device i believe is a secondary

 

i had this issue once a long time ago i think setting the static ip inside the dhcp range worked. which i found weir, but whatever works right.

_____

some other things you can try without get ahold of your isp.

 

namebench

its a dns testing software

 

try a different router or if you have a system with 2 or ethernet or more connections you can use something untangle (should run a like a linux livecd from usb or smoothwall)

then you can use you pc hardware as a router and custom firewall. of course for you it would just be for testing proposes .