ISO CLNS Commands: clear clns cache Through distance (ISO CLNS)

This chapter explains the function and syntax of the International Organization for Standardization (ISO) Connectionless Network Services (CLNS) protocol commands: clear clns cache through distance (ISO CLNS). For more information about defaults and usage guidelines, see the corresponding chapter of the Cisco IOS Apollo Domain, Banyan VINES, DECnet, ISO CLNS, and XNS Command Reference, Release 12.1.

c lear clns cache

To clear and reinitialize the CLNS routing cach, use the clear clns cache command in EXEC mode.

clear clns cache

Syntax Description

This command has no arguments or keywords.

clear clns es-neighbors

To remove end system (ES) neighbor information from the adjacency database, use the clear clns es-neighbors command in EXEC mode.

clear clns es-neighbors

Syntax Description

This command has no arguments or keywords.

clear clns is-neighbors

To remove intermediate system (IS) neighbor information from the adjacency database, use the clear clns is-neighbors command in EXEC mode.

clear clns is-neighbors

Syntax Description

This command has no arguments or keywords.

clear clns neighbors

To remove CLNS neighbor information from the adjacency database, use the clear clns neighbors command in EXEC mode.

clear clns neighbors

Syntax Description

This command has no arguments or keywords.

clear clns route

To remove all of the dynamically derived CLNS routing information, use the clear clns route command in EXEC mode.

clear clns route

Syntax Description

This command has no arguments or keywords.

clear tarp counters

To clear all Target Identifier Address Resolution Protocol (TARP) counters that are shown with the show tarp traffic command, use the clear tarp counters command in EXEC mode.

clear tarp counters

Syntax Description

This command has no arguments or keywords.

clear tarp ldb-table

To clear the system ID-to-sequence number mapping entries stored in the TARP loop-detection buffer table, use the clear tarp ldb-table command in EXEC mode.

clear tarp ldb-table

Syntax Description

This command has no arguments or keywords.

clear tarp tid-table

To clear the dynamically created TARP target identifier (TID)-to-NSAP address mapping entries stored in the TID cache, use the clear tarp tid-table command in EXEC mode.

clear tarp tid-table

Syntax Description

This command has no arguments or keywords.

clns access-group

To filter transit CLNS traffic going either into or out of the router or both on a per-interface basis, use the clns access-group command in interface configuration mode. To disable filtering of transit CLNS packets, use the no form of this command.

clns access-group name [in | out]

no clns access-group name [in | out]

Syntax Description

name

Name of the filter set or expression to apply.

in

(Optional) Filter should be applied to CLNS packets entering the router.

out

(Optional) Filter should be applied to CLNS packets leaving the router. If you do not specify an in or out keyword, out is assumed.

name	Name of the filter set or expression to apply.
in	(Optional) Filter should be applied to CLNS packets entering the router.
out	(Optional) Filter should be applied to CLNS packets leaving the router. If you do not specify an in or out keyword, out is assumed.

clns adjacency-filter

To filter the establishment of CLNS ES and IS adjacencies, use the clns adjacency-filter command in interface configuration mode. To disable this filtering, use the no form of this command.

clns adjacency-filter {es | is} name

no clns adjacency-filter {es | is} name

Syntax Description

es

ES adjacencies are to be filtered.

is

IS adjacencies are to be filtered.

name

Name of the filter set or expression to apply.

es	ES adjacencies are to be filtered.
is	IS adjacencies are to be filtered.
name	Name of the filter set or expression to apply.

clns checksum

To enable checksum generation when ISO CLNS routing software sources a CLNS packet, use the clns checksum command in interface configuration mode. To disable checksum generation, use the no form of this command.

clns checksum

no clns checksum

Syntax Description

This command has no arguments or keywords.

clns cluster-alias

To advertise the same system ID as other systems in ES hello messages, use the clns cluster-alias command in interface configuration mode to allow multiple systems. To disable cluster aliasing, use the no form of this command.

clns cluster-alias

no clns cluster-alias

Syntax Description

This command has no arguments or keywords.

clns configuration-time

To specify the rate at which ES hellos and IS hellos are sent, use the clns configuration-time command in global configuration mode. To restore the default value, use the no form of this command.

clns configuration-time seconds

no clns configuration-time

Syntax Description

seconds

Rate in seconds at which ES and IS hello packets are sent.

seconds	Rate in seconds at which ES and IS hello packets are sent.

clns congestion-threshold

To set the congestion experienced bit if the output queue has more than the specified number of packets in it, use the clns congestion-threshold command in interface configuration mode. A number value of zero or the no form of this command prevents this bit from being set. To remove the parameter setting and set it to 0, use the no form of this command.

clns congestion-threshold number

no clns congestion-threshold

Syntax Description

number

Number of packets that are allowed in the output queue before the system sets the congestion-experienced bit. The value zero (0) prevents this bit from being set.

number	Number of packets that are allowed in the output queue before the system sets the congestion-experienced bit. The value zero (0) prevents this bit from being set.

clns dec-compatible

To allow IS hellos sent and received to ignore the N-selector byte, use the clns dec-compatible command in interface configuration mode. To disable this feature, use the no form of this command.

clns dec-compatible

no clns dec-compatible

Syntax Description

This command has no arguments or keywords.

clns enable

If you do not intend to perform any static or dynamic routing on an interface, but intend to pass ISO CLNS packet traffic to end systems, use the clns enable command in interface configuration mode. To disable ISO CLNS on a particular interface, use the no form of this command.

clns enable

no clns enable

Syntax Description

This command has no arguments or keywords.

clns erpdu-interval

To determine the minimum interval time, in milliseconds, between error ERPDUs, use the clns erpdu-interval command in interface configuration mode. A milliseconds value of zero or the no form of this command turns off the interval and effectively sets no limit between ERPDUs.

clns erpdu-interval milliseconds

no clns erpdu-interval milliseconds

Syntax Description

milliseconds

Minimum interval time (in milliseconds) between ERPDUs.

milliseconds	Minimum interval time (in milliseconds) between ERPDUs.

clns esct-time

To supply an ES configuration timer option in a transmitted IS hello packet that tells the ES how often it should transmit ES hello packet PDUs, use the clns esct-time command in interface configuration mode. To restore the default value and disable this function, use the no form of this command.

clns esct-time seconds

no clns esct-time seconds

Syntax Description

seconds

Time, in seconds, between ES hello PDUs. Range is from 0 to 65535.

seconds	Time, in seconds, between ES hello PDUs. Range is from 0 to 65535.

clns es-neighbor

To list all systems that will be used when you manually specify the NSAP-to-SNPA mapping, use the clns es-neighbor command in interface configuration mode. The SNPAs are the MAC addresses. To delete the ES neighbor, use the no form of this command.

clns es-neighbor nsap snpa

no clns es-neighbor nsap

Syntax Description

nsap

Specific NSAP to map to a specific MAC address.

snpa

Data link (MAC) address.

nsap	Specific NSAP to map to a specific MAC address.
snpa	Data link (MAC) address.

clns filter-expr

To combine CLNS filter sets and CLNS address templates to create complex logical NSAP pattern-matching expressions, use one or more clns filter-expr commands in global configuration mode. To delete the expression, use the no form of this command.

clns filter-expr ename [term | not term | term [and | or | xor] term]

no clns filter-expr ename

Syntax Description

ename

Alphanumeric name to apply to this filter expression.

not

(Optional) Defines a filter expression that is pattern matched only if the pattern given by term is not matched.

or

(Optional) Defines a filter expression that is pattern matched if either of the patterns given by the two terms is matched.

and

(Optional) Defines a filter expression that is pattern matched only if both of the patterns given by the two terms are matched.

xor

(Optional) Defines a filter expression that is pattern matched only if one of the patterns, but not both, given by the two terms are matched.

term

Filter expression term. A term can be any of the following:

ename---Another, previously defined, filter expression.

sname (or destination sname)---A previously defined filter set name, with the filter set applied to the destination NSAP address.

source sname---A previously defined filter set name, with the filter set applied to the source NSAP address.

ename	Alphanumeric name to apply to this filter expression.
not	(Optional) Defines a filter expression that is pattern matched only if the pattern given by term is not matched.
or	(Optional) Defines a filter expression that is pattern matched if either of the patterns given by the two terms is matched.
and	(Optional) Defines a filter expression that is pattern matched only if both of the patterns given by the two terms are matched.
xor	(Optional) Defines a filter expression that is pattern matched only if one of the patterns, but not both, given by the two terms are matched.
term	Filter expression term. A term can be any of the following: ename---Another, previously defined, filter expression. sname (or destination sname)---A previously defined filter set name, with the filter set applied to the destination NSAP address. source sname---A previously defined filter set name, with the filter set applied to the source NSAP address.

clns filter-set

To build a list of CLNS address templates with associated permit and deny conditions for use in CLNS filter expressions, use the clns filter-set command in global configuration mode. CLNS filter expressions are used in the creation and use of CLNS access lists. To delete the entire filter set, use the no form of this command.

clns filter-set name [permit | deny] template

no clns filter-set name

Syntax Description

name

Alphanumeric name to apply to this filter set.

permit | deny

(Optional) Addresses matching the pattern specified by template are to be permitted or denied. If neither permit nor deny is specified, permit is assumed.

template

Address template, template alias name, or the keyword default. Address templates and alias names are described under the description of the clns template-alias global configuration command. The default keyword denotes a zero-length prefix and matches any address.

name	Alphanumeric name to apply to this filter set.
permit \| deny	(Optional) Addresses matching the pattern specified by template are to be permitted or denied. If neither permit nor deny is specified, permit is assumed.
template	Address template, template alias name, or the keyword default. Address templates and alias names are described under the description of the clns template-alias global configuration command. The default keyword denotes a zero-length prefix and matches any address.

clns holding-time

To allow the sender of an ES hello or IS hello to specify the length of time you consider the information in the hello packets to be valid, use the clns holding-time command in global configuration mode. To restore the default value (300 seconds, or 5 minutes), use the no form of this command.

clns holding-time seconds

no clns holding-time

Syntax Description

seconds

Length of time in seconds during which the information in the hello packets is considered valid.

seconds	Length of time in seconds during which the information in the hello packets is considered valid.

clns host

To define a name-to-NSAP mapping that can then be used with commands requiring NSAPs, use the clns host command in global configuration mode.

clns host name nsap

Syntax Description

name

Desired name for the NSAP. The first character can be either a letter or a number, but if you use a number, the operations you can perform are limited.

nsap

NSAP to which that the name maps.

name	Desired name for the NSAP. The first character can be either a letter or a number, but if you use a number, the operations you can perform are limited.
nsap	NSAP to which that the name maps.

clns is-neighbor

To list all intermediate systems that will be used when you manually specify the NSAP-to-SNPA mapping, use the clns is-neighbor command in interface configuration mode. The SNPAs are the MAC addresses. To delete the specified IS neighbor, use the no form of this command.

clns is-neighbor nsap snpa

no clns is-neighbor nsap

Syntax Description

nsap

NSAP of a specific intermediate system to enter as neighbor to a specific MAC address.

snpa

Data link (MAC) address.

nsap	NSAP of a specific intermediate system to enter as neighbor to a specific MAC address.
snpa	Data link (MAC) address.

clns mtu

To set the maximum transmission unit (MTU) packet size for the interface, use the clns mtu command in interface configuration mode. To restore the default and maximum packet size, use the no form of this command.

clns mtu bytes

no clns mtu

Syntax Description

bytes

Maximum packet size in bytes. The minimum value is 512; the default and maximum packet size depend on the interface type.

bytes	Maximum packet size in bytes. The minimum value is 512; the default and maximum packet size depend on the interface type.

clns net (global)

To assign a static address for a router, use the clns net command in global configuration mode. If the Cisco IOS software is configured to support ISO CLNS, but is not configured to dynamically route CLNS packets using ISO IGRP or IS-IS, use this command to assign an address to the router. To remove any previously configured NET or NSAP address, use the no form of this command.

clns net {net-address | name}

no clns net {net-address | name}

Syntax Description

net-address

NET address.

name

CLNS host name to be associated with this interface.

net-address	NET address.
name	CLNS host name to be associated with this interface.

clns net (interface)

To assign an NSAP address or name to a router interface, use the clns net command in interface configuration mode. If the Cisco IOS software is configured to support ISO CLNS, but is not configured to dynamically route CLNS packets using an ISO IGRP or IS-IS, use this command to assign an address to the router. To remove any previously configured NSAP address, use the no form of this command.

clns net {nsap-address | name}

no clns net {nsap-address | name}

Syntax Description

nsap-address

Specific NSAP address.

name

Name to be associated with this interface.

nsap-address	Specific NSAP address.
name	Name to be associated with this interface.

clns packet-lifetime

To specify the initial lifetime for locally generated packets, use the clns packet-lifetime command in global configuration mode. To remove the parameter's settings, use the no form of this command.

clns packet-lifetime seconds

no clns packet-lifetime

Syntax Description

seconds

Packet lifetime in seconds.

seconds	Packet lifetime in seconds.

clns rdpdu-interval

To determine the minimum interval time between redirect PDUs (RDPDUs), use the clns rdpdu-interval command in interface configuration mode. A milliseconds value of zero or the no form of this command turns off the interval rate and effectively sets no limit between RDPDUs.

clns rdpdu-interval milliseconds

no clns rdpdu-interval milliseconds

Syntax Description

milliseconds

Minimum interval time (in milliseconds) between RDPDUs.

milliseconds	Minimum interval time (in milliseconds) between RDPDUs.

clns route (create)

To create an interface static route, use this form of the clns route command in global configuration mode. To remove this route, use the no form of this command.

clns route nsap-prefix type number [snpa-address]

no clns route nsap-prefix

Syntax Description

nsap-prefix

Network service access point prefix. This value is entered into a static routing table and used to match the beginning of a destination NSAP. The longest NSAP-prefix entry that matches is used.

type

Interface type.

number

Interface number.

snpa-address

(Optional) Specific SNPA address. Optional for serial links; required for multiaccess networks.

nsap-prefix	Network service access point prefix. This value is entered into a static routing table and used to match the beginning of a destination NSAP. The longest NSAP-prefix entry that matches is used.
type	Interface type.
number	Interface number.
snpa-address	(Optional) Specific SNPA address. Optional for serial links; required for multiaccess networks.

clns route (enter)

To enter a specific static route, use this form of the clns route command in global configuration mode. NSAPs that start with nsap-prefix are forwarded to next-hop-net or the name of the next hop. To remove this route, use the no form of this command.

clns route nsap-prefix {next-hop-net | name}

no clns route nsap-prefix

Syntax Description

nsap-prefix

Network service access point prefix. This value is entered into a static routing table and used to match the beginning of a destination NSAP. The longest NSAP-prefix entry that matches is used.

next-hop-net

Next-hop NET. This value is used to establish the next hop of the route for forwarding packets.

name

Name of the next hop node. This value can be used instead of the next-hop NET to establish the next hop of the route for forwarding packets.

nsap-prefix	Network service access point prefix. This value is entered into a static routing table and used to match the beginning of a destination NSAP. The longest NSAP-prefix entry that matches is used.
next-hop-net	Next-hop NET. This value is used to establish the next hop of the route for forwarding packets.
name	Name of the next hop node. This value can be used instead of the next-hop NET to establish the next hop of the route for forwarding packets.

clns route-cache

To allow fast switching through the cache, use the clns route-cache command in interface configuration mode. To disable fast switching, use the no form of this command.

clns route-cache

no clns route-cache

Syntax Description

This command has no arguments or keywords.

clns route default

To configure a default zero-length prefix rather than type an NSAP prefix, use the clns route default command in global configuration mode. To remove this route, use the no form of this command.

clns route default nsap-prefix type number

no clns route default

Syntax Description

nsap-prefix

Network service access point prefix that is a default zero-length prefix.

type

Interface type. Specify the interface type immediately followed by the interface number; there is no space between the two.

number

Interface number.

nsap-prefix	Network service access point prefix that is a default zero-length prefix.
type	Interface type. Specify the interface type immediately followed by the interface number; there is no space between the two.
number	Interface number.

clns route discard

To explicitly tell a router to discard packets with NSAP addresses that match the specified nsap-prefix, use the clns route discard command in global configuration mode. To remove this route, use the no form of this command.

clns route nsap-prefix discard

no clns route nsap-prefix

Syntax Description

nsap-prefix

Network service access point prefix. This value is entered into a static routing table and used to match the beginning of a destination NSAP. The longest NSAP-prefix entry that matches is used.

discard

The router discards packets with NSAPs that match the specified value for the nsap-prefix argument.

nsap-prefix	Network service access point prefix. This value is entered into a static routing table and used to match the beginning of a destination NSAP. The longest NSAP-prefix entry that matches is used.
discard	The router discards packets with NSAPs that match the specified value for the nsap-prefix argument.

clns router isis

To configure an Intermediate System-to-Intermediate System (IS-IS) routing process for International Standards Organization (ISO) Connectionless Network Service Protocol (CLNS) on a specified interface and to attach an area designator to the routing process, use the clns router isis command in interface configuration mode. To disable IS-IS for ISO, use the no form of the command.

clns router isis area-tag

no clns router isis area-tag

Syntax Description

area-tag

Required for multiarea IS-IS configuration. Optional for conventional IS-IS configuration.

Defines a meaningful name for an area routing process. If not specified, a null tag is assumed. It must be unique among all CLNS router processes for a given router. The area-tag argument is used later as a reference to this area routing process.

Each area in a multiarea configuration should have a non-null area tag to facilitate identification of the area.

area-tag	Required for multiarea IS-IS configuration. Optional for conventional IS-IS configuration. Defines a meaningful name for an area routing process. If not specified, a null tag is assumed. It must be unique among all CLNS router processes for a given router. The area-tag argument is used later as a reference to this area routing process. Each area in a multiarea configuration should have a non-null area tag to facilitate identification of the area.

clns router iso-igrp

To specify ISO IGRP routing on a specified interface, use the clns router iso-igrp command in interface configuration mode. To disable ISO IGRP routing for the system, use the no form of the global configuration command with the appropriate tag.

clns router iso-igrp tag [level 2]

no clns router iso-igrp tag

Syntax Description

tag

Meaningful name for routing process. It must be unique among all CLNS router processes for a given router. This tag should be the same as defined for the routing process in the router iso-igrp global configuration command.

level 2

(Optional) Allows the interface to advertise Level 2 information.

tag	Meaningful name for routing process. It must be unique among all CLNS router processes for a given router. This tag should be the same as defined for the routing process in the router iso-igrp global configuration command.
level 2	(Optional) Allows the interface to advertise Level 2 information.

clns routing

To enable routing of CLNS packets, use the clns routing command in global configuration mode. To disable CLNS routing, use the no form of this command.

clns routing

no clns routing

Syntax Description

This command has no arguments or keywords.

clns security pass-through

To allow the Cisco IOS software to pass packets that have security options set, use the clns security pass-through command in global configuration mode. To disable this function, use the no form of this command.

clns security pass-through

no clns security pass-through

Syntax Description

This command has no arguments or keywords.

clns send-erpdu

To allow CLNS to send an error PDU when the routing software detects an error in a data PDU, use the clns send-erpdu command in interface configuration mode. To disable this function, use the no form of this command.

clns send-erpdu

no clns send-erpdu

Syntax Description

This command has no arguments or keywords.

clns send-rdpdu

To allow CLNS to redirect PDUs (RDPDUs) when a better route for a given host is known, use the clns send-rdpdu command in interface configuration mode. To disable this function, use the no form of this command.

clns send-rdpdu

no clns send-rdpdu

Syntax Description

This command has no arguments or keywords.

clns split-horizon

To implement split horizon for ISO IGRP updates, use the clns split-horizon command in interface configuration mode. To disable this function, use the no form of this command.

clns split-horizon

no clns split-horizon

Syntax Description

This command has no arguments or keywords.

clns template-alias

To build a list of alphanumeric aliases of CLNS address templates for use in the definition of CLNS filter sets, use one or more clns template-alias commands in global configuration mode. To delete the alias, use the no form of this command.

clns template-alias name template

no clns template-alias name

Syntax Description

name

Alphanumeric name to apply as an alias for the template.

template

Address template.

name	Alphanumeric name to apply as an alias for the template.
template	Address template.

clns want-erpdu

To specify whether to request ERPDUs on packets sourced by the router, use the clns want-erpdu command in global configuration mode. To remove the parameter settings, use the no form of this command.

clns want-erpdu

no clns want-erpdu

Syntax Description

This command has no arguments or keywords.

distance (ISO CLNS)

To configure the administrative distance for CLNS routes learned, use the distance command in router configuration mode. To restore the administrative distance to the default, use the no form of this command.

distance value [clns]

no distance value [clns]

Syntax Description

value

Administrative distance, indicating the trustworthiness of a routing information source. This argument has a numerical value between 0 and 255. A higher relative value indicates a lower trustworthiness rating. Preference is given to routes with smaller values. The default, if unspecified, is 110.

clns

(Optional) CLNS-derived routes for IS-IS.

value	Administrative distance, indicating the trustworthiness of a routing information source. This argument has a numerical value between 0 and 255. A higher relative value indicates a lower trustworthiness rating. Preference is given to routes with smaller values. The default, if unspecified, is 110.
clns	(Optional) CLNS-derived routes for IS-IS.

Table of Contents

ISO CLNS Commands: clear clns cache Through distance (ISO CLNS)