Weird network issue

Hello everyone,

I've been trying to troubleshoot this with my boss, but I'm stumped. Here's the issue:

We have laptops, Chrome books, and iPads. The laptops can connect to the internet and browse like normal. The Chromebooks and iPads can only connect to certain websites, while the majority of them "sit and spin" while loading.

We've checked our ISP, our firewall, and rebooted the switches and APs, but that didn't help. The laptops (both mac and PC) are running as normal.

Any ideas?

Thanks.

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Comments

darkerz

How's your DNS and IP Configuration look like side by side?

zidian

wargamer6 wrote: »

The Chromebooks and iPads can only connect to certain websites, while the majority of them "sit and spin" while loading.

Definitely sounds like a DNS issue. Check the DNS servers configured on each. I'd venture that the ones that aren't working are using a different DNS server. If it is set to configure automatically, try setting it manually.

wargamer6

We tried using Google's DNS and had no luck. Same with other 3rd party ones.

darkerz

Has this worked before?
Has anyone changed anything

networker050184

Sounds like a possible MTU/MSS issue.

wargamer6

darkerz wrote: »

Has this worked before?
Has anyone changed anything ?

Was working fine until today.

no!all!

Have you tried turning it off and back on again?

...I just had to!

keenon

networker050184 wrote: »

Sounds like a possible MTU/MSS issue.

agreed , seen this one before as well

wargamer6

keenon wrote: »

agreed , seen this one before as well

How would one being troubleshooting that? I'm a network newbie.

Obdurate

wargamer6 wrote: »

How would one being troubleshooting that? I'm a network newbie.

The first question that I always ask is "what changed?" You said that the Chromebooks were working and then they were not, so what changed from the last time they worked until now?

Did you add a web filter?
Did you add a new firewall?
Are you using a proxy server? Or a global proxy server?
Did you add new wireless Access Points? Are those APs doing NAT?
What changed on your DNS server(s)? (I suspect this is where the issue is by the way)
Is there a rogue AP on your network? (This happens way to often)

Testing your Chromebooks:

What is your Chromebook's IP address? Is it the proper range?
From your Chromebook can you ping another device?
Can you ping your gateway?
Can you ping your public IP Address?
Can you ping your DNS server(s)?
Pull up a browser and go 199.181.132.249, did disney's website appear?
Pull up a browser and type disney.com did the website appear?
Run a tracert from your Chromebook to Google's DNS at 8.8.8.8, does the trace stop at a device on your LAN?

Obdurate~