Can' t access one web site

[#1]

Hi, i have a Fortigate 60, just upgraded to 3.0 MR1. First i wasnt abel do access some https Sites, so i did the tcp-mss MTU 1492. Now the https Sites are displayes, great! But i am not sure where to write what MTU Number. My provider said that for a T-DSL buisiness with fixed IP, i need a MTU=1456. So in the Fortigat Web GUI at WAN1 -> MTU 1456 and on the CLI the set tcp-mss 1456 too? Or in the Web GUI the dafault MTU -> 1500 and on the CLI the set tcp-mss 1456 too? Is that right? TH reason is, i still cant access one website -> http://www.eb2-quicktrip.com/BT/GetFareFlightJS.do?lang=de Works fine without Fortigate, but with the fortigate connect, no webpage is displayed. Any ideas? Thank, Tim Harms

[player]

Hey Tim, Usually the MTU value is set on the interface that is connected to the service provider, try to remove the mtu value from interface lan and check.

[#3]

HI Player, the checkbox " override default MTU value" on the lan interface is disabled, so the default value 1500 is used - on the ISP Side the value is 1456. Any more ideas? Greetings Tim

[player]

Hey Tim, try to fine tune the mtu value - i use 1394 although my isp told that they using 1445, regards, player

[#5]

Maybe this can help; http://kc.forticare.com/default.asp?id=1731&SID=&Lang=1 First of all I am using pppoe connection with MTU=1492, internal network MTU is 1500. But be about the article carefull: I was experiencing connection problem with msn. I tried the lower tcp-mss as written in article but I was unsuccessful because the example in the article may be wrong or lead misunderstandings. It is written that: " ...the following example changes the MSS value from 1460 to 1452 when leaving the PPPoE interface and eventually reaches the web server" and the example is: ------------------------------------- config system interface edit " internal" set ip 192.168.1.99 255.255.255.0 set tcp-mss 1492 next ------------------------------------- in my opinion it must be set tcp-mss 1452 My configuration worked with tcp-mss=1452 Note: mss is mtu-40 bytes as written in article. Regards, Batuhan Kısacıkoglu

[player]

guys, please note that these setting may vary on each ISP and on the type of the internet connection dsl,cable etc.. player.

[#7]

Yes you are absolutely right. For that reason I first write my configuration. Then let' s be specific :). For Tim' s case the MTU for WAN is 1456. So he should configure his " internal" lan tcp-mss as 1416. Regards. Batuhan