Network troubleshooting

[spelaben]

Hey guys, I have some trouble with my home network and I'm running out of ideas. I don't like to ask for help but here I am, a little desperate as well to be honest.

The network components:

Switch (10 clients, 1 server (Windows Server 2008 R2 with AD/DNS/DHCP), 1 router)

Now I bought a new Router (ASUS AC66U) for the second floor, which I configured as Accesspoint so I can use WLAN, also connected to the switch.

I flashed DD-WRT and everything seemed to work fine, but sporadically I lose Internet connectivity on my WLAN connected devices. Later I discovered, that I also lose connection on my clients when that happens.

I ran a wireshark capture on one of the clients and what happens now (reproducible) is that when I open a URL I get lots of TCP DUP ACK and TCP RETRANSMISSION packets, the site opens very slowly, if at all. Now the interesting part: When I turn off the AC66U and open up a site it instantly loads and there are maybe 1-2 retransmission packets.

I didn't run the wireshark trace on other firmwares I tried (ASUSWRT Merlin, stock firmware and TomatoUSB by Shibby) but the symptoms are the same.

In the source of the packets I see the MAC adress of the first router, which connects to my ISP and I guess there is some kind of conflict but I am by no means an expert to network related stuff.

I would greatly appreciate it if someone could guide me through the setup of DD-WRT to coexist peacefully with the other router or give me some useful hints on how to solve this problem.

Thanks! Please let me know if you need more information on the setup.

 

[stevech]

Hey guys, I have some trouble with my home network and I'm running out of ideas. I don't like to ask for help but here I am, a little desperate as well to be honest.

The network components:

Switch (10 clients, 1 server (Windows Server 2008 R2 with AD/DNS/DHCP), 1 router)

Now I bought a new Router (ASUS AC66U) for the second floor, which I configured as Accesspoint so I can use WLAN, also connected to the switch.

I flashed DD-WRT and everything seemed to work fine, but sporadically I lose Internet connectivity on my WLAN connected devices. Later I discovered, that I also lose connection on my clients when that happens.

I ran a wireshark capture on one of the clients and what happens now (reproducible) is that when I open a URL I get lots of TCP DUP ACK and TCP RETRANSMISSION packets, the site opens very slowly, if at all. Now the interesting part: When I turn off the AC66U and open up a site it instantly loads and there are maybe 1-2 retransmission packets.

I didn't run the wireshark trace on other firmwares I tried (ASUSWRT Merlin, stock firmware and TomatoUSB by Shibby) but the symptoms are the same.

In the source of the packets I see the MAC adress of the first router, which connects to my ISP and I guess there is some kind of conflict but I am by no means an expert to network related stuff.

I would greatly appreciate it if someone could guide me through the setup of DD-WRT to coexist peacefully with the other router or give me some useful hints on how to solve this problem.

Thanks! Please let me know if you need more information on the setup.

have you isolated the fault to be in the WiFi and not the router-ISP-modem?
Can you use the devices without DD-WRT? (manufacturer's AP mode?)

 

[abailey]

Are both routers wireless?

 

[synchron]

Hey guys, I have some trouble with my home network and I'm running out of ideas. I don't like to ask for help but here I am, a little desperate as well to be honest.

The network components:

Switch (10 clients, 1 server (Windows Server 2008 R2 with AD/DNS/DHCP), 1 router)

Now I bought a new Router (ASUS AC66U) for the second floor, which I configured as Accesspoint so I can use WLAN, also connected to the switch.

I flashed DD-WRT and everything seemed to work fine, but sporadically I lose Internet connectivity on my WLAN connected devices. Later I discovered, that I also lose connection on my clients when that happens.

I ran a wireshark capture on one of the clients and what happens now (reproducible) is that when I open a URL I get lots of TCP DUP ACK and TCP RETRANSMISSION packets, the site opens very slowly, if at all. Now the interesting part: When I turn off the AC66U and open up a site it instantly loads and there are maybe 1-2 retransmission packets.

I didn't run the wireshark trace on other firmwares I tried (ASUSWRT Merlin, stock firmware and TomatoUSB by Shibby) but the symptoms are the same.

In the source of the packets I see the MAC adress of the first router, which connects to my ISP and I guess there is some kind of conflict but I am by no means an expert to network related stuff.

I would greatly appreciate it if someone could guide me through the setup of DD-WRT to coexist peacefully with the other router or give me some useful hints on how to solve this problem.

Thanks! Please let me know if you need more information on the setup.

Have you ever solved this? I have the same router and same problem.

 

[System Error Message]

retransmit means that there was either packet loss or errors.