topic Re: TCP MSS Adjustment in Security Gateway in Spark Firewall (SMB)

TCP MSS Adjustment in Security Gateway

tamzida — Sun, 03 Jul 2022 07:01:29 GMT

How to set TCP MSS value in a specific interface from security gateway of Quantum 1600 appliance with running OS version R80.20.35 .Current environment there is no Security Management Server so I cannot edit it from GuiDBEdit.

Re: TCP MSS Adjustment in Security Gateway

G_W_Albrecht — Sun, 03 Jul 2022 08:53:10 GMT

Look here: sk108199: Internal host cannot surf the Internet when MTU of the WAN port is less than 1400

More reading: sk61221: Issues requiring adjustment of the Maximum Segment Size (MSS) of TCP SYN and TCP SYN-ACK packets on Security Gateway

Re: TCP MSS Adjustment in Security Gateway

tamzida — Sun, 03 Jul 2022 10:01:27 GMT

When I trying to enable TCP MSS getting the following error
#fw ctl set int fw_clamp_tcp_mss
Set operation failed: failed to get parameter fw_clamp_tcp_mss

Re: TCP MSS Adjustment in Security Gateway

G_W_Albrecht — Sun, 03 Jul 2022 20:52:31 GMT

[Expert@fifteenfifty]# fw ctl get int fw_clamp_tcp_mss

fw_clamp_tcp_mss = 0

[Expert@fifteenfifty]# ver

This is Check Point's 1550 Appliance R80.20.40 - Build 665

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[Expert@seven-eleven]# fw ctl get int fw_clamp_tcp_mss

fw_clamp_tcp_mss = 0

[Expert@seven-eleven]# ver

This is Check Point's 730 Appliance R77.20.87 - Build 120

Re: TCP MSS Adjustment in Security Gateway

Chris_Atkinson — Tue, 26 Jul 2022 16:13:46 GMT

fw ctl set int fw_clamp_tcp_mss 1