Asus RT-AC1900 conflicts with Meraki MX100

[StevenSun]

I have an ASUS RT-AC1900 router connect to MX100, and the internet speed on ASUS RT-AC1900 router is very slow. I test the internet speed by using ping command, and I get a lots of package lost. When I connect to MX100 directly, the internet speed is fast and doesn't lost package when using ping command. I wondered if MX100 has something that conflicts with ASUS RT-AC1900 router. 

Is there anyone has this issue? Or I configured something wrong in MX100?

[MerakiDave]

I'll assume the MX100 is mostly at the default configurations, and the Asus router for example is not being impacted by a group policy or traffic shaping rule?  It doesn't sound like there's any type of throughput issue with the MX100, since you mentioned you can connect directly to it and it's very fast with no packet loss.  But then when you have your Asus router plugged in things get very slow... is that wireless or wired?  Just like you plugged directly into an MX100 LAN interface and ran a speed test, can you connect the Asus WAN/Internet port to one of the MX100 LAN ports, and then connect into the Asus router on a wired connection (just like you did with the MX100) and run a speed test from there?  If that's also fast with no packet loss, then examine the wireless config on the Asus.  If it's also slow, then check the other non-wireless settings.  I'd suggest also running an actual speed test and not rely only on ping output.

[StevenSun]

Hi MerikaDave,

Thank you for your quickly reply. All I connected is wired not wireless. Yes, I did connect ASUS router directly to Meraki lan ports, and the testing result is same and it is very slow. I also used speedtest.net website to test the speed, sometimes was normal and sometimes even can not open the page. The MX100 is mostly at the default configurations, and I didn't configured traffic shaping rule. 

[MerakiDave]

Are there any other devices you can connect to the LAN side of the MX100 and get normal/fast speeds, in order to isolate the slowness to the Asus router?  Also, what if you bypass the MX100 temporarily, and uplink the Asus router right to your ISP connection, and then connect a machine to a LAN port on the Asus and see if speed tests are still slow.  If they are, it's something in the Asus config.  If not, it's something between the Asus WAN port and MX100.

Also, if you bypass the MX100 and only have the Asus in line and it's normal & fast, as another temporary test, try reversing the connectivity.  Connect the Asus to your ISP, and then connect the MX100 WAN interface to the Asus on a LAN interface, and then connect into an MX100 LAN port and run a speed test.

If none of those things reveal any clues, perhaps revert back to the original connectivity you wanted with the MX100, connect the Asus and reproduce the slowness, perhaps open a case with Meraki Support who can assist with some further troubleshooting, packet capture, etc.

[StevenSun]

Hi MerakiDave,

This ASUS router works with another Cisco router just not Meraki. I connected my laptop to the lan port on Meraki directly (bypass ASUS router), and the internet speed is normal.  I don't have chance to do much more testing. I don't know if someone has similar issue.