Brocade Communications Systems Brocade ICX 6650 6650 User Manual

Page 109

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Brocade ICX 6650 Security Configuration Guide

89

53-1002601-01

Standard named ACL configuration

NOTE

To specify the host name instead of the IP address, the host name must be configured using the
DNS resolver on the Brocade device. To configure the DNS resolver name, use the ip dns
server-address… command at the global CONFIG level of the CLI.

The wildcard parameter specifies the mask value to compare against the host address specified by
the source-ip parameter. The wildcard is in dotted-decimal notation (IP address format). It is a
four-part value, where each part is 8 bits (one byte) separated by dots, and each bit is a one or a
zero. Each part is a number ranging from 0 to 255, for example 0.0.0.255. Zeros in the mask mean
the packet source address must match the source-ip. Ones mean any value matches. For example,
the source-ip and wildcard values 10.157.22.26 0.0.0.255 mean that all hosts in the Class A
subnet 10.157.22.x match the policy.

If you prefer to specify the wildcard (mask value) in CIDR format, you can enter a forward slash after
the IP address, then enter the number of significant bits in the mask. For example, you can enter
the CIDR equivalent of “10.157.22.26 0.0.0.255” as “10.157.22.26/24”. The CLI automatically
converts the CIDR number into the appropriate ACL mask (where zeros instead of ones are the
significant bits) and changes the non-significant portion of the IP address into ones. For example, if
you specify 10.157.22.26/24 or 10.157.22.26 0.0.0.255, then save the changes to the
startup-config file, the value appears as 10.157.22.0/24 (if you have enabled display of subnet
lengths) or 10.157.22.0 0.0.0.255 in the startup-config file.

If you enable the software to display IP subnet masks in CIDR format, the mask is saved in the file
in “/mask-bits” format. To enable the software to display the CIDR masks, enter the ip
show-subnet-length command at the global CONFIG level of the CLI. You can use the CIDR format to
configure the ACL entry regardless of whether the software is configured to display the masks in
CIDR format.

NOTE

If you use the CIDR format, the ACL entries appear in this format in the running-config and
startup-config files, but are shown with subnet mask in the display produced by the show ip
access-list command.

The host source-ip | hostname parameter lets you specify a host IP address or name. When you
use this parameter, you do not need to specify the mask. A mask of all zeros (0.0.0.0) is implied.

The any parameter configures the policy to match on all host addresses.

The log argument configures the device to generate syslog entries and SNMP traps for inbound
packets that are denied by the access policy.

NOTE

You can enable logging on inbound ACLs and filters that support logging even when the ACLs and
filters are already in use. To do so, re-enter the ACL or filter command and add the log parameter to
the end of the ACL or filter. The software replaces the ACL or filter command with the new one. The
new ACL or filter, with logging enabled, takes effect immediately.

The in | out parameter applies the ACL to incoming or outgoing traffic on the interface to which you
apply the ACL. You can apply the ACL to an Ethernet port or virtual interface.

NOTE

If the ACL is bound to a virtual routing interface, you also can specify a subset of ports within the
VLAN containing that interface when assigning an ACL to the interface. See

“Enabling ACL filtering

based on VLAN membership or VE port membership”

on page 109 for further details.

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