Brocade Communications Systems Brocate Ethernet Access Switch 6910 - Manual (Page 293)

Brocade 6910 Ethernet Access Switch Configuration Guide 243
53-1002581-01
IPv4 ACLs
11
dport – Protocol
4
destination port number. (Range: 0-65535)
port-bitmask – Decimal number representing the port bits to match. (Range: 0-65535)
control-flags – Decimal number (representing a bit string) that specifies flag bits in byte 14
of the TCP header. (Range: 0-63)
flag-bitmask – Decimal number representing the code bits to match.
time-range-name - Name of the time range. (Range: 1-30 characters)
Default Setting
None
Command Mode
Extended IPv4 ACL
Command Usage
• All new rules are appended to the end of the list.
• Address bit masks are similar to a subnet mask, containing four integers from 0 to 255, each
separated by a period. The binary mask uses 1 bits to indicate “match” and 0 bits to indicate
“ignore.” The bit mask is bitwise ANDed with the specified source IP address, and then
compared with the address for each IP packet entering the port(s) to which this ACL has been
assigned.
• You can specify both Precedence and ToS in the same rule. However, if DSCP is used, then
neither Precedence nor ToS can be specified.
• The control-code bitmask is a decimal number (representing an equivalent bit mask) that is
applied to the control code. Enter a decimal number, where the equivalent binary bit “1”
means to match a bit and “0” means to ignore a bit. The following bits may be specified:
• 1 (fin) – Finish
• 2 (syn) – Synchronize
• 4 (rst) – Reset
• 8 (psh) – Push
• 16 (ack) – Acknowledgement
• 32 (urg) – Urgent pointer
For example, use the code value and mask below to catch packets with the following flags set:
• SYN flag valid, use “control-code 2 2”
• Both SYN and ACK valid, use “control-code 18 18”
• SYN valid and ACK invalid, use “control-code 2 18”
Example
This example accepts any incoming packets if the source address is within subnet 10.7.1.x. For
example, if the rule is matched; i.e., the rule (10.7.1.0 & 255.255.255.0) equals the masked
address (10.7.1.2 & 255.255.255.0), the packet passes through.
Console(config-ext-acl)#permit 10.7.1.1 255.255.255.0 any
Console(config-ext-acl)#