Strange behavior on latest merlin

[ghostek]

I have strange behavior with my ac88u. I have latest version of merlin installed with ab-solution, pixelsrv, dnscrypt and skynet. I've got a one client on my network that serve webserver on port 80 (192.168.0.10). Only for local purposes. Now when I try open chrome directly from other computer in the local network I got timeout on this address. But when I connect from mobile phone using mobile connection through open vpn I can open website without problems Any suggestion what is going on?

 

[kfp]

What if you use your mobile phone through wireless locally?

 

[agilani]

I have strange behavior with my ac88u. I have latest version of merlin installed with ab-solution, pixelsrv, dnscrypt and skynet. I've got a one client on my network that serve webserver on port 80 (192.168.0.10). Only for local purposes. Now when I try open chrome directly from other computer in the local network I got timeout on this address. But when I connect from mobile phone using mobile connection through open vpn I can open website without problems Any suggestion what is going on?

Can you ping the webserver from other computers inside the network?
Is the phone using a nat'd address for the website? Do you have port forwarding enabled? What happens if you telnet to that webserver on port 80? What happens if you open a browser on the webserver and type 127.0.0.1? Did you look at netstat to see what ip address the webserver is listening in on? Is the webserver setup to check for host headers or will it respond to ip address directly?

 

[ghostek]

Ok, here are scenarios:
Webserver: 192.168.0.10:80

1. Windows 10, Desktop PC - 192.168.0.3 = no connection
2. Window 10, Laptop - 192.168.0.4 = no connection
3. Window 10, Desktop PC at work - 10.8.0.2 OpenVPN = ok
4. Android (mobile phone), outside home - 10.8.0.3 OpenVPN = ok
5. Android (same mobile phome), 192.168.0.5 at home = no connection
6. ssh to assus and ping 192.168.0.10 =
PING 192.168.0.10 (192.168.0.10): 56 data bytes
64 bytes from 192.168.0.10: seq=0 ttl=64 time=2.633 ms
64 bytes from 192.168.0.10: seq=1 ttl=64 time=2.560 ms


7. ssh to assus and telnet 192.168.0.10 =
Content-Type: application/octet-stream
Content-Length: 0
Connection: close

Ping from android, and windows 10 gives:
Pinging 192.168.0.10 with 32 bytes of data:
Request timed out.
Request timed out.

This website is served only for local purposes. Do I need rely port forwarding? I don't want that this site be available on the internet.

 

[agilani]

No, you don't need port forwarding. Just want to make sure you didn't have any port forwarding on dmz features enabled.

And sorry if I'm being redundant. Are you pinging the server from the other workstations on the 192.168.0.0 subnet? Or was that the telnet test? These tests would show two different things. I want to see if ping is working to decide if we need to troubleshoot arp resolution of the ip address or if the port is not listening on the right ip address.

what is the webserver running? Can you provide and ipconfig /all or ifconfig and a netstat -a or netstat -l from the server?

Also, what is the ip address and subnet of your router lan interface?

from what you are describing so far, my guess is that this is an arp resolution issue. Do an arp -a on one of the workstations after you trying to ping the address and you should see a listing with the ip and mac address of the server.

 

[ghostek]

This is an Amplituner, I dont have access to server, sorry I made telnet test to port 80 to check if I can access this port from router. This is a full response from telnet check from ac88.
telnet 192.168.0.10:80
GET
HTTP/1.1 400 Bad Request
Server: Network_Module/1.0 (R-N803D)
Content-Type: application/octet-stream
Content-Length: 0
Connection: close

Ip address of router is 192.168.0.1 in lan (so subnet is 192.168.0.* with mask 255.255.255.0). I have dhcp configured to give ips from range 192.168.0.50 - 150 and all other devices has assigned static ip addresses. So this device has 192.168.0.10.

arp -a from laptop:
Interface: 192.168.0.5 --- 0x9
Internet Address Physical Address Type
192.168.0.1 b0-6e-bf-6b-3a-b8 dynamic
192.168.0.2 b0-6e-bf-6b-3a-b8 dynamic
192.168.0.12 64-eb-8c-90-b6-b7 static
192.168.0.255 ff-ff-ff-ff-ff-ff static
224.0.0.22 01-00-5e-00-00-16 static
224.0.0.251 01-00-5e-00-00-fb static
224.0.0.252 01-00-5e-00-00-fc static
239.255.255.250 01-00-5e-7f-ff-fa static
255.255.255.255 ff-ff-ff-ff-ff-ff static

Interface: 172.23.255.161 --- 0xb
Internet Address Physical Address Type
224.0.0.22 01-00-5e-00-00-16 static
224.0.0.251 01-00-5e-00-00-fb static
224.0.0.252 01-00-5e-00-00-fc static
239.255.255.250 01-00-5e-7f-ff-fa static
255.255.255.255 ff-ff-ff-ff-ff-ff static

Interface: 169.254.80.80 --- 0x15
Internet Address Physical Address Type
169.254.255.255 ff-ff-ff-ff-ff-ff static
224.0.0.22 01-00-5e-00-00-16 static
224.0.0.251 01-00-5e-00-00-fb static
224.0.0.252 01-00-5e-00-00-fc static
239.255.255.250 01-00-5e-7f-ff-fa static


on ip 192.168.0.2 is pixelserv

============
arp -a on assus return

? (192.168.0.90) at 04:b1:67:0a:86:3a [ether] on br0
android-de47f5d9e2cd7433 (192.168.0.51) at cc:c3:ea:56:4e:1b [ether] on br0
HarmonyHub (192.168.0.87) at 00:04:20:fa:c8:c0 [ether] on br0
Google-Home-Mini (192.168.0.88) at e4:f0:42:09:04:54 [ether] on br0
R-N803D (192.168.0.10) at 34:15:13:67:e1:e4 [ether] on br0
Drukarka (192.168.0.12) at 64:eb:8c:90:b6:b7 [ether] on br0
Chromecast-Audio (192.168.0.74) at 54:60:09:e1:10:14 [ether] on br0
TL-WA860RE (192.168.0.73) at c6:25:e9:3e:65:57 [ether] on br0
sho-laptop (192.168.0.5) at 08:3e:8e:3e:5a:cf [ether] on br0
Google-Home (192.168.0.60) at f4:f5:d8:da:00:74 [ether] on br0
=====

Like you see the result are different and I don't know what is going on. All devices are connected to assus by wifi 2.4ghz

 

[ColinTaylor]

All devices are connected to assus by wifi 2.4ghz

Do you have "Set AP Isolated" set to Yes under Wireless - Professional? Are you using guest networks?

 

[ghostek]

Both disabled.
After restart of router it works for a fev seconds and then stops.

 

[agilani]

Both disabled.
After restart of router it works for a fev seconds and then stops.

your workstation arp table does not show the device at all. Did you trying pinging the server before you pulled it? I assume this is the mac address of your device from the asus router. R-N803D (192.168.0.10) at 34:15:13:67:e1:e4 . What happens if you put a static arp entry into your workstation?

This may be an issue with arp resolution. The reason it works over vpn is that most likely the vpn clients are being nat'd behind the ip address of the asus router.

Did you put any static dhcp addresses for the server or otherwise for that mac address?

If you really want to troubleshoot it
1) check and see if entering a static mac entry in your arp table fixes the problem
2) install wireshark on the workstation and wipe the arp table and do a network caputre to see if you see the arp request and reply.
3) Since you entered the ip address of the server manually check the subnet mask as well. You want to make sure the server, router, and workstation are all still on the same broadcast domain.

 

[agilani]

Both disabled.
After restart of router it works for a fev seconds and then stops.

You checked the settings for both 5ghz and 2.4ghz?

 

[ghostek]

Yes, 5 an 2.4 have disabled AP Isolation and guest networks.

 

[Da.Rock]

Had the dame issue and had to do a factory reset followed by manual configuration to get it resolved.

 

[ghostek]

But I've already made factory reset twice :/

 

[ghostek]

Ok, I found that I am not the only one with this bug :/
https://github.com/RMerl/asuswrt-merlin.ng/issues/154

 

[kfp]

This may be an issue with arp resolution.

Also think this is the case.

@ghostek Can you try turning on IGMP snooping on the 2.4Ghz? There were users having problems with connecting their Yatse remote with their Kodi instances, and turning it on helped.

 

[agilani]

@ghostek
have you tried these steps yet?

your workstation arp table does not show the device at all. Did you trying pinging the server before you pulled it? I assume this is the mac address of your device from the asus router. R-N803D (192.168.0.10) at 34:15:13:67:e1:e4 . What happens if you put a static arp entry into your workstation?

This may be an issue with arp resolution. The reason it works over vpn is that most likely the vpn clients are being nat'd behind the ip address of the asus router.

Did you put any static dhcp addresses for the server or otherwise for that mac address?

If you really want to troubleshoot it
1) check and see if entering a static mac entry fixes the problem in your arp table
2) install wireshark on the workstation and wipe the arp table and do a network caputre to see if you see the arp request and reply.
3) Since you entered the ip address of the server manually check the subnet mask as well. You want to make sure the server, router, and workstation are all still on the same broadcast domain.

 

[ghostek]

@agilani
1) I configured this device and set static ip. I also put mac and static IP on dhcp section in router configuration page (but why on dhcp if client has manual config?). Is this ok? Because nothing changed.

2) First of all, I must learn how to use wireshark and what to look for

3) This settings I checked many times. All are correct. All devices are on same subnet and have same mask.

 

[agilani]

Did you add the static arp entry in the workstation? Technically speaking you shouldn't have to do any of this and the router should always do a gratuitous arp for anything it knows about. There is something definitely off with this version of the asus code. A static arp entry will not fix the problem, but if it works...you'll know for sure it is an arp problem and you've mitigated the symptom.

on windows command prompt (will probably need admin command prompt)

arp -s 157.55.85.212 00-aa-00-62-c6-09


Something else to try is to downgrade to 380.69_2 or 380.70 - most of the weird behavior i've noticed is on the new asus code base. I'm just trying to stick with it to see if I can get an engineer from asus to take a look.

 

[ghostek]

@agilani sorry that I don't answer but I was not at home. I back yesterday. So I checked this cmd arp -s but this not helps. I noticed one thing. When I ping this address from router side using ssh and telnet to this address to port 80 and send GET command, it shows immediately on windows computer side. Eg when I check arp -a I see this client with postfix "dynamic" and I can access website and ping. When I reset router I must do the same thing (Ping, telnet operation).

 

[Karl Perkins]

I've hit the exact same issue - and reported it here...
https://www.snbforums.com/threads/arping-is-unreliable-for-wireless-clients.55799/
Seems like its more common than I thought! Is there any reliable way out of this, or is it inherently a bug from Asus code?