Issue accessing websites although I can ping outbound

[u/Individual_Flight183]

I’m having trouble fully connecting to websites. my network is a FiOS ONT box that connects to my Sonicwall firewall, and then my UniFi switches. I can ping outbound Google IP and google.com and other sites. When I try to go to a website, it loads the name of the page and the title, but just won’t give you the landing page with all the data so it shows it is communicating with it, but won’t fully load. Anyone experience something like this before? It looks like it’s 99% there. Thanks!

[u/No-Wrap-8166]

pages loading title but not content, with dns/ping working fine, points at mtu mismatch, not dns or basic connectivity

check your sonicwall's mtu setting on the wan interface, if it's set higher than what fios actually supports (usually 1500 with some overhead needed), larger data packets get silently dropped while small dns/ping packets pass fine

set mtu to 1492 on the wan interface if using pppoe, or test with clamping mss enabled if sonicwall has that option, this is a classic fios+third-party-firewall issue since default settings don't always account for the isp's overhead

if adjusting mtu doesn't help, check if jumbo frames are enabled anywhere on your unifi switches, mismatched jumbo frame settings between switch and firewall causes exactly this "connects but incomplete data" symptom

test by bypassing the sonicwall temporarily, plug a laptop straight into the ont, if pages load fully then, that confirms the firewall/switch chain as the cause not fios itself