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Chapter 30 Configuring Network Security with ACLs
Configuring IPv4 ACLs
Troubleshooting ACLs
If this ACL manager message appears and [chars] is the access-list name,
ACLMGR-2-NOVMR: Cannot generate hardware representation of access list [chars]
The switch has insufficient resources to create a hardware representation of the ACL. The resources
include hardware memory and label space but not CPU memory. A lack of available logical operation
units or specialized hardware resources causes this problem. Logical operation units are needed for a
TCP flag match or a test other than
eq
(
ne
,
gt
,
lt
, or
range
) on TCP, UDP, or SCTP port numbers.
Use one of these workarounds:
•
Modify the ACL configuration to use fewer resources.
•
Rename the ACL with a name or number that alphanumerically precedes the ACL names or
numbers.
To determine the specialized hardware resources, enter the
show platform layer4 acl map
privileged
EXEC command. If the switch does not have available resources, the output shows that index 0 to
index 15 are not available.
For more information about configuring ACLs with insufficient resources, see CSCsq63926 in the Bug
Toolkit.
For example, if you apply this ACL to a VLAN interface:
permit tcp
source source-wildcard
destination destination-wildcard
range 5 60
permit tcp
source source-wildcard
destination destination-wildcard
range 15 160
permit tcp
source source-wildcard
destination destination-wildcard
range 115 1660
permit tcp
source source-wildcard
destination destination-wildcard
And if this message appears:
ACLMGR-2-NOVMR: Cannot generate hardware representation of access list [chars]
The flag-related operators are not available. To avoid this issue,
•
Move the fourth ACE before the first ACE by using
ip access-list resequence
global configuration
command:
permit tcp
source source-wildcard
destination destination-wildcard
permit tcp
source source-wildcard
destination destination-wildcard
range 5 60
permit tcp
source source-wildcard
destination destination-wildcard
range 15 160
permit tcp
source source-wildcard
destination destination-wildcard
range 115 1660
or
•
Rename the ACL with a name or number that alphanumerically precedes the other ACLs (for
example, rename ACL
79
to ACL
1
).
You can now apply the first ACE in the ACL to the VLAN interface. The switch allocates the ACE to
available mapping bits in the Opselect index and then allocates flag-related operators to use the same
bits in the TCAM.
IPv4 ACL Configuration Examples
This section provides examples of configuring and applying IPv4 ACLs. For detailed information about
compiling ACLs, see the
Cisco IOS Security Configuration Guide, Release 12.2
and to the Configuring
IP Services” section in the “IP Addressing and Services” chapter of the
Cisco IOS IP Configuration
Guide, Release 12.2.
Содержание Catalyst 2928
Страница 28: ...Contents xxviii Catalyst 2928 Switch Software Configuration Guide OL 23389 01 ...
Страница 32: ...xxx Catalyst 2928 Switch Software Configuration Guide OL 23389 01 Preface ...
Страница 496: ...26 14 Catalyst 2928 Switch Software Configuration Guide OL 23389 01 Chapter 26 Configuring SPAN Displaying SPAN Status ...
Страница 534: ...29 18 Catalyst 2928 Switch Software Configuration Guide OL 23389 01 Chapter 29 Configuring SNMP Displaying SNMP Status ...
Страница 700: ...Index IN 36 Catalyst 2928 Switch Software Configuration Guide OL 23389 01 ...