Blocking in non default VLAN?

[ToTT]

Hello, i am a complete amateur in networking. And I got problem when running DNS Benchmark, but only in non default VLAN.

Basically, my default VLAN1 interface is 192.168.1.2, connected to router in 192.168.1.1 and also as default gateway. Then, I have VLAN2 with subnet 192.168.2.0. I also make IPv4 Static Routes 0.0.0.0/0 to 192.168.1.1.

I can browse internet, etc. when connected in VLAN2.

BUT, when I am connected in VLAN2, I get this error from DNS Benchmark: "Internet connectivity was lost while benchmarking". But, when I am in VLAN1, this error doesn't appear. 

So, something must have been blocking in VLAN2, right?

What should I do? Thank you. 

[Giuseppe Larosa]

Hello @ToTT ,

can you explain your network setup ?

are the end user devices in vlan2 processed by NAT only once or two times ?

Can you provide a reference link to the DNS benchmark tool you have used it may have a FAQ section that may contain the answer to your question .

If users in vlan2 are able to access the public Internet your configuration is correct.

Hope to help

Giuseppe

[ToTT]

Hi Giuseppe,

Thanks for trying to help.

Here is my network diagram:

ISP---modem/router---router---SG350---VLAN1 and VLAN2

Basically, old modem/router doesn't have bridge mode, so I use another router to be able to NAT the VLAN2. 

I am using router that has DDWRT firmware, DDWRT firmware has option to NAT the static route of VLAN2 (without this option, VLAN2 cannot get to internet). So, yes, user in VLAN2 can access internet. But, something is wrong because Benchmark cannot finish good.

Here is the DNS Benchmark that I was talking about. 

https://www.grc.com/dns/benchmark.htm

[Giuseppe Larosa · Accepted solution]

Hello @ToTT ,

to be honest I have never used this DNS benchmark tool.

However, if you are able to run it on Vlan1 as the web site explains the results depend on your location so even if you are not able to run it on vlan2 you can assume that the same results would be achieved on it.

The device performing NAT for Vlan2 may have a built in rate limiter in terms of packets per seconds of DNS traffic and this is likely the reason why the test fails.

I would not worry about this.

Hope to help

Giuseppe

[ToTT]

I see, I was just worried if VLAN2 has worse internet connection. Thank you for your help, Giuseppe!