Alcatel-Lucent 7750 SR-OS, Configuration Manual

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Filter Policies
7750 SR OS Router Configuration Guide Page 511
tcp-ack
Syntax tcp-ack { true | false }
no tcp-ack
Context config>filter>ip-filter>entry > match
config>filter>ipv6-filter>entry>match
Description
This command configures matching on the ACK bit being set or reset in the control bits of the TCP
header of an IP packet as an IP filter match criterion. Note that an entry containing Layer 4 match
criteria will not match non-initial (2nd, 3rd, etc) fragments of a fragmented packet since only the first
fragment contains the Layer 4 information.
The no form of the command removes the criterion from the match entry.
Default no tcp-ack
Parameters true — Specifies matching on IP packets that have the ACK bit set in the control bits of the TCP
header of an IP packet.
false — Specifies matching on IP packets that do not have the ACK bit set in the control bits of the
TCP header of the IP packet.
tcp-syn
Syntax tcp-syn { true | false }
no tcp-syn
Context config>filter>ip-filter>entry > match
config>filter>ipv6-filter>entry>match
Description This command configures matching on the SYN bit being set or reset in the control bits of the TCP
header of an IP packet as an IP filter match criterion. Note that an entry containing Layer 4 match
criteria will not match non-initial (2nd, 3rd, etc) fragments of a fragmented packet since only the first
fragment contains the Layer 4 information.
The SYN bit is normally set when the source of the packet wants to initiate a TCP session with the
specified destination IP address.
The no form of the command removes the criterion from the match entry.
Default no tcp-syn
Parameters true — Specifies matching on IP packets that have the SYN bit set in the control bits of the TCP
header.
false — Specifies matching on IP packets that do not have the SYN bit set in the control bits of the
TCP header.