Asus RT A68U DNS and connection issues

[no1baggiesfan]

Got this router yesterday flashed newest asus firmware, reset then newest merlin.
connected SH2 in modem mode then router.
searched the new until my eyes hurt lol, cannot figure this out
router works fine for 5 mins then drops connection, it could work for 2 hours then it drops, also having serious DNS issues with this router/firmware, websites will not load, I get the "DNS cannot be resolved" message.
its wired and wifi connections dropping, like the router has been turned off.

There is no Internet connection
Try:

• Checking the network cables, modem, and router
• Reconnecting to Wi-Fi
• Running Windows Network Diagnostics

DNS_PROBE_FINISHED_NO_INTERNET


SH2 is in modem mode but TBH I get less issues if its in normal mode ?? no idea how.




Asus RT A68u router using latest merlin firmware
DNS servers are set to :8.8.8.8 and 8.8.8.4 in wan and lan
turned off QOS made a little difference (slightly more stable)

looking through the logs there is a weird issue where the date changes, I see this a lot in the logs, never had the router in August lol, so I have no idea

eg:

May 8 13:04:31 kernel: usbcore: deregistering interface driver usblp
May 8 13:04:31 kernel: usblp0: removed
Aug 1 01:00:13 syslogd started: BusyBox v1.25.1
Aug 1 01:00:13 kernel: klogd started: BusyBox v1.25.1 (2017-03-29 00:40:13 EDT)
Aug 1 01:00:13 kernel: Linux version 2.6.36.4brcmarm (merlin@ubuntu-dev) (gcc version 4.5.3 (Buildroot 2012.02) ) #2 SMP PREEMPT Wed Mar 29 00:48:32 EDT 2017
Aug 1 01:00:13 kernel: CPU: ARMv7 Processor [413fc090] revision 0 (ARMv7), cr=10c53c7f
Aug 1 01:00:13 kernel: CPU: VIPT nonaliasing data cache, VIPT nonaliasing instruction cache

 

[Jack Yaz]

Put SH2 (presumably Virgin media?) in modem mode, then connect by ethernet from SH2 to WAN port on 68U. Then can you attach screenshot of your WAN page from Asus UI please?

The date changes are where NTP is dropping I suspect. Do you have any USB devices attached to the router? Also please provide syslog content when the DNS errors occur.

 

[no1baggiesfan]

Put SH2 (presumably Virgin media?) in modem mode, then connect by ethernet from SH2 to WAN port on 68U. Then can you attach screenshot of your WAN page from Asus UI please?

The date changes are where NTP is dropping I suspect. Do you have any USB devices attached to the router? Also please provide syslog content when the DNS errors occur.

I have a usb printer attached "Samsung CLP-310"
DNS errors seem completely random TBH, happened about 7 times last night in a 2 hour spell, also had the same this morning when PC was first turned on, took about 2 minutes to get a web page to load.

LOL, its just done it again while I was typing this reply, nothing in logs tho

 

[Jack Yaz]

Did you fill in the MAC address? I have it blank with my SH3

Oh and can you send me a screenshot of the LAN -> DHCP page please

 

[no1baggiesfan]

Did you fill in the MAC address? I have it blank with my SH3

Oh and can you send me a screenshot of the LAN -> DHCP page please

mac was empty, I filled it in after reading about a similar issue, someone suggested trying it to see if it made any difference.

 

[uberAC]

I've had a long-standing similar issue with my AC68u. It loses it's ability to resolve DNS every few minutes. It only affects the 2.4GHz channel. It does not happen on 5GHz or ethernet connections. When running Windows Network Diagnostics, it generally reports a problem with DNS.

I found that I can use the Merlin firmware 378.54 and older and the problem does not occur. As soon as I update the firmware, whether Merlin or ASUS OE firmware, the problem immediately returns.

I've kind of given up battling it and bought and installed a new router yesterday -- no more woes.

 

[Jack Yaz]

mac was empty, I filled it in after reading about a similar issue, someone suggested trying it to see if it made any difference.

You don't need to specify the DNS in LAN, since it's already set in the WAN. Leave the LAN DHCP DNS blank, which will direct clients to talk to your router for DNS, rather than straight to upstream Google. Change "advertise router for DNS" to yes.

 

[no1baggiesfan]

You don't need to specify the DNS in LAN, since it's already set in the WAN. Leave the LAN DHCP DNS blank, which will direct clients to talk to your router for DNS, rather than straight to upstream Google. Change "advertise router for DNS" to yes.

those were more settings from an article I read, they were changed after all the issues I had last night, but I have changed them again re your advice
will see how we go, never had this many issues with a bloody router, if it doesnt behave its getting binned for an R7000 or a linksys 7500 lol

 

[Jack Yaz]

Next time it goes down we really need to see what syslog is doing, i've been running an 87U for a couple weeks and it's flawless, even with me throwing scripts at it!

 

[no1baggiesfan]

Next time it goes down we really need to see what syslog is doing, i've been running an 87U for a couple weeks and it's flawless, even with me throwing scripts at it!

Ive "looked" at the logs a couple of times after an "outage" but at the time of the last outage there is nothing there, last one happened 39 mins ago, but the log is blank for 30 mins at that time, 15 minutes before and after it occurred.

 

[Jack Yaz]

Try changing to OpenDNS, I had some issues with Google DNS at work the other day

 

[no1baggiesfan]

Try changing to OpenDNS, I had some issues with Google DNS at work the other day

another of "last nights changes" lol
previously I left it blank, will change to opendns and see how we go

thanks for the help Jack, hopefully we will have "less" issues now

 

[Jack Yaz]

another of "last nights changes" lol
previously I left it blank, will change to opendns and see how we go

thanks for the help Jack, hopefully we will have "less" issues now

No worries, leave LAN DNS blank and enter OpenDNS into the WAN. Presumably you've rebooted the client and/or flushed its DNS since installing the new router?

 

[no1baggiesfan]

No worries, leave LAN DNS blank and enter OpenDNS into the WAN. Presumably you've rebooted the client and/or flushed its DNS since installing the new router?

??? lol
umm, rebooted PC and router a few times, flushed DNS ? no.

just googled it "ipconfig /flushdns" in cmd window ? done it though

 

[Jack Yaz]

??? lol
umm, rebooted PC and router a few times, flushed DNS ? no.

just googled it "ipconfig /flushdns" in cmd window ? done it though

Rebooting the PC should clear things down, but doesn't hurt to force a flush between changing DNS. Windows likes to cache things!

 

[no1baggiesfan]

well, its been fine for the last few hours, just had my first "hiccup"

May 8 23:06:32 disk_monitor: Got SIGALRM... (no net for 20 secs)
had another (very small 2-3 secs)
May 8 23:57:13 openvpn[4004]: WARNING: 'link-mtu' is used inconsistently, local='link-mtu 1558', remote='link-mtu 1542'
May 8 23:57:13 openvpn[4004]: WARNING: 'cipher' is used inconsistently, local='cipher AES-128-CBC', remote='cipher BF-CBC'


that was the only item in the log at the time of the issue, previous msg was 2 hours ago, something to do with the vpn setup serverside.

sigalarm ? no idea lol, other than that dip, everything seems to be fine (fingers crossed, toes crossed)

update. turned on pc this morning, no internet took a full 4 mins before I could load this page, DNS error again, I usually have 6-7 tabs that start with chrome, every single one gave same error "this websites DNS could not be found" grrr

This site can’t be reached
www.google.co.uk’s server DNS address could not be found.

• Try running Windows Network Diagnostics.

DNS_PROBE_FINISHED_NXDOMAIN

not sure how relevant this is but... this was in logs:
May 9 10:04:18 dnsmasq-dhcp[4072]: DHCPRELEASE(br0) 192.168.1.6
May 9 10:04:18 dnsmasq-dhcp[4072]: DHCPDISCOVER(br0) 192.168.1.6
May 9 10:04:18 dnsmasq-dhcp[4072]: DHCPOFFER(br0) 192.168.1.6
May 9 10:04:18 dnsmasq-dhcp[4072]: DHCPREQUEST(br0) 192.168.1.6
May 9 10:04:18 dnsmasq-dhcp[4072]: DHCPACK(br0) 192.168.1.6
DESKTOP-Q6S2HU8
May 9 10:06:12 dnsmasq-dhcp[4072]: DHCPREQUEST(br0) 192.168.1.6
May 9 10:06:12 dnsmasq-dhcp[4072]: DHCPACK(br0) 192.168.1.6
DESKTOP-Q6S2HU8
May 9 10:11:17 dnsmasq-dhcp[4072]: DHCPREQUEST(br0) 192.168.1.6
May 9 10:11:17 dnsmasq-dhcp[4072]: DHCPACK(br0) 192.168.1.6
DESKTOP-Q6S2HU8
May 9 10:15:07 dnsmasq-dhcp[4072]: DHCPREQUEST(br0) 192.168.1.6
May 9 10:15:07 dnsmasq-dhcp[4072]: DHCPACK(br0) 192.168.1.6
DESKTOP-Q6S2HU8
May 9 10:17:19 dnsmasq-dhcp[4072]: DHCPREQUEST(br0) 192.168.1.6
May 9 10:17:19 dnsmasq-dhcp[4072]: DHCPACK(br0) 192.168.1.6
DESKTOP-Q6S2HU8

 

[no1baggiesfan]

just trying to reply to this thread and guess what ? lol, lost connection on this PC, internet hasn't gone off for other devices, just this one.

tried 3x to up;oad a log.txt file, everytime I select the file, I lose the connection, wondering if its related ?

cannot attach txt file, so I will post here:
May 9 19:44:27 openvpn[4004]: [6ecab10dac93519e70ce075ed477e546] Inactivity timeout (--ping-restart), restarting
May 9 19:44:27 openvpn[4004]: SIGUSR1[soft,ping-restart] received, process restarting
May 9 19:44:32 openvpn[4004]: WARNING: No server certificate verification method has been enabled. See http://openvpn.net/howto.html#mitm for more info.
May 9 19:44:32 openvpn[4004]: NOTE: the current --script-security setting may allow this configuration to call user-defined scripts
May 9 19:44:32 openvpn[4004]: TCP/UDP: Preserving recently used remote address: [AF_INET]************
May 9 19:44:32 openvpn[4004]: UDP link local: (not bound)
May 9 19:44:32 openvpn[4004]: UDP link remote: [************
May 9 19:44:32 openvpn[4004]: WARNING: 'link-mtu' is used inconsistently, local='link-mtu 1558', remote='link-mtu 1542'
May 9 19:44:32 openvpn[4004]: WARNING: 'cipher' is used inconsistently, local='cipher AES-128-CBC', remote='cipher BF-CBC'
May 9 19:44:32 openvpn[4004]: [6ecab10dac93519e70ce075ed477e546] Peer Connection Initiated with [AF_INET]************
May 9 19:44:33 openvpn[4004]: AUTH: Received control message: AUTH_FAILED
May 9 19:44:33 openvpn[4004]: vpnrouting.sh tun11 1500 1622 ************ init
May 9 19:44:34 openvpn-routing: Configuring policy rules for client 1
May 9 19:44:34 openvpn-routing: Removing rule 10101 from routing policy
May 9 19:44:34 openvpn-routing: Flushing client routing table
May 9 19:44:34 openvpn-routing: Completed routing policy configuration for client 1
May 9 19:44:34 openvpn[4004]: ERROR: Linux route delete command failed: external program exited with error status: 2
May 9 19:44:34 openvpn[4004]: ERROR: Linux route delete command failed: external program exited with error status: 2
May 9 19:44:34 openvpn[4004]: ERROR: Linux route delete command failed: external program exited with error status: 2
May 9 19:44:34 openvpn[4004]: /usr/sbin/ip addr del dev tun11 local ************ peer ************

 

[no1baggiesfan]

May 9 20:04:09 dnsmasq-dhcp[4072]: DHCPACK(br0) 192.168.1.60 ************ android-918da7ae16a929be
May 9 20:11:24 dnsmasq-dhcp[4072]: DHCPREQUEST(br0) 192.168.1.131 ************
May 9 20:11:24 dnsmasq-dhcp[4072]: DHCPACK(br0) 192.168.1.131 ************ iPhone
May 9 20:18:31 dnsmasq-dhcp[4072]: DHCPDISCOVER(br0) ************
May 9 20:18:31 dnsmasq-dhcp[4072]: DHCPOFFER(br0) 192.168.1.60 ************
May 9 20:18:31 dnsmasq-dhcp[4072]: DHCPREQUEST(br0) 192.168.1.60 ************
May 9 20:18:31 dnsmasq-dhcp[4072]: DHCPACK(br0) 192.168.1.60 ************ android-918da7ae16a929be
May 9 20:25:13 dnsmasq-dhcp[4072]: DHCPREQUEST(br0) 192.168.1.6 ************
May 9 20:25:13 dnsmasq-dhcp[4072]: DHCPACK(br0) 192.168.1.6 ************ DESKTOP-Q6S2HU8

 

[Jack Yaz]

What scripts are you running? Also, are you routing everything via a VPN?

 

[no1baggiesfan]

as far as im aware I have no scripts running, vpn is not tunneling PC

No idea what is wrong with router/pc but its flakey as hell tonight, DNS and disconnects every 5 minutes.

log is full of these:

May 9 21:19:06 dnsmasq-dhcp[4072]: DHCPREQUEST(br0) 192.168.1.6 (mac removed)
May 9 21:19:06 dnsmasq-dhcp[4072]: DHCPACK(br0) 192.168.1.6 *** **** DESKTOP-Q6S2HU8

another problem I have noticed, is everytime I start up my PC or restart it, I have to wait 2 mins for connection, this cannot be right, my SH2 was never that slow, pages used to load up with the pc