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			14 lines
		
	
	
		
			678 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			14 lines
		
	
	
		
			678 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| .. cfgcmd:: set interfaces {{ var0 }} <interface> {{ var2 }} {{ var3 }}
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|   {{ var5 }} {{ var6 }} adjust-mss <mss>
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| 
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|   As Internet wide PMTU discovery rarely works, we sometimes need to clamp our
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|   TCP MSS value to a specific value. This is a field in the TCP options part of
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|   a SYN packet. By setting the MSS value, you are telling the remote side
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|   unequivocally 'do not try to send me packets bigger than this value'.
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| 
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|   .. note:: This command was introduced in VyOS 1.4 - it was previously called:
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|     ``set firewall options interface <name> adjust-mss <value>``
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| 
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|   .. hint:: MSS value = MTU - 20 (IP header) - 20 (TCP header), resulting in
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|     1452 bytes on a 1492 byte MTU.
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