Juniper ACX2000 Configuration Guide

Table 73: Standard Firewall Filter Match Conditions for IPv4 Traffic on ACX Series
Routers (continued)
DescriptionMatch Condition
Match one or more of the low-order 6 bits in the 8-bit TCP flags field in the TCP header.
To specify individual bit fields, you can specify the following text synonyms or hexadecimal
values:
•
fin (0x01)
•
syn (0x02)
•
rst (0x04)
•
push (0x08)
•
ack (0x10)
•
urgent (0x20)
In a TCP session, the SYN flag is set only in the initial packet sent, while the ACK flag is set in
all packets sent after the initial packet.
You can string together multiple flags using the bit-field logical operators.
For combined bit-field match conditions, see the tcp-initial match conditions.
If you configure this match condition, we recommend that you also configure the protocol tcp
match statement in the same term to specify that the TCP protocol is being used on the port.
tcp-flags value
Match the initial packet of a TCP connection. This is an alias for tcp-flags "(!ack & syn)".
This condition does not implicitly check that the protocol is TCP. If you configure this match
condition, we recommend that you also configure the protocol tcp match condition in the same
term.
tcp-initial
Match the IPv4 time-to-live number. Specify a TTL value or a range of TTL values. For number,
you can specify one or more values from 2 through 255.
ttl number
Related
Documentation
Guidelines for Configuring Firewall Filters on page 1044•
• Standard Firewall Filter Match Conditions and Actions on ACX Series Routers Overview
on page 1052
• Standard Firewall Filter Terminating Actions on ACX Series Routers on page 1063
• Standard Firewall Filter Nonterminating Actions on ACX Series Routers on page 1064
Standard Firewall Filter Match Conditions for IPv6 Traffic on ACX Series Routers
You can configure a firewall filter with match conditions for Internet Protocol version 6
(IPv6) traffic (familyinet6). Table 74 on page 1058 describes the match conditions you can
configure at the [edit firewall family inet6 filter filter-name term term-name from] hierarchy
level.
1057Copyright © 2017, Juniper Networks, Inc.
Chapter 32: Configuring Firewall Filters

Juniper ACX2000 Specifications

General

Brand	Juniper
Model	ACX2000
Category	Network Router
Language	English