Clients behind the RB are unable to load yahoo.com or facebook.com “most of the time”. I have run across a few threads suggesting:
/ ip firewall mangle add chain=forward protocol=tcp tcp-flags=syn tcp-mss=1361-65535 action=change-mss new-mss=1360 disabled=no
But this does not fix the issue here. Client is using broadband connection, using local dns cache and public DNS servers 8.8.8.8 and 8.8.4.4.
Very frustrating, and client is ready to scream… Has anybody some ideas?
Thank you,
Andrew
We need these answers to continue:
Are your clients connected directly to a LAN? Or are they PPPoE customers?
Is your upstream ISP a DSL service or is it a cable service?
Always make sure your DNS “Max UDP Packet Size” is 4096. What was yours set at?
Clients are connected directly to LAN. The ISP is broadband, MTU 1500.
No settings have been changed from default as far as local MTU settings.
In the Mikrotik:
Set your DNS Servers to 8.8.8.8 and 8.8.4.4
Always set your DNS “Max UDP Packet Size” to 4096.
On the PC’s, make sure they use your mikrotik’s IP (or 8.8.8.
as their DNS server.
If this fixes the issue, then you know that it was a DNS problem… which is what it sounds like.