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Digital Equipment Corporation developed the DECnet protocol to provide a way for its computers to communicate with one another. Currently in its fifth major product release, DECnet Phase V is a superset of the Open System Interconnection (OSI) protocol suite, supports all OSI protocols, and is compatible with the previous release (Phase IV). DECnet Phase IV Prime supports inherent MAC addresses, which allow DECnet nodes to coexist with systems running other protocols that have MAC address restrictions. DECnet support on Cisco routers includes local-area and wide-area DECnet Phase IV routing over Ethernet, Token Ring, FDDI, and serial lines such as X.25, Frame Relay, and Switched Multimegabit Data Service (SMDS).
Use the commands in this chapter to configure and monitor DECnet networks. For DECnet protocol configuration information and examples, refer to the "Configuring DECnet" chapter of the Cisco IOS Apollo Domain, Banyan VINES, DECnet, ISO CLNS, and XNS Configuration Guide.
 |
Note Not all Cisco access servers support DECnet. For more information, refer to the release notes for the current Cisco IOS release. |
Syntax Description
access-list-number Integer you choose between 300 and 399 that uniquely identifies the access list. permit Permits access when there is an address match. deny Denies access when there is an address match. source Source address. DECnet addresses are written in the form area.node. For example, 50.4 is node 4 in area 50. All addresses are in decimal. source-mask Mask to be applied to the address of the source node. All masks are in decimal. destination (Optional) Destination node's DECnet address in decimal format. DECnet addresses are written in the form area.node. For example, 50.4 is node 4 in area 50. destination-mask (Optional) Destination mask. DECnet addresses are written in the form area.node. For example, 50.4 is node 4 in area 50. All masks are in decimal.
Defaults
No access list is defined.
Command Modes
Global configuration
Command History
10.0 This command was introduced.
Release
Modification
Examples
The following example configures access list 301 to allow traffic from any host in networks 1 and 3. It implies no other traffic is permitted. (The end of a list contains an implicit "deny all else" statement.)
access-list 301 permit 1.0 0.1023 0.0 63.1023 access-list 301 permit 3.0 0.1023 0.0 63.1023
Related Commands
Creates an access list that filters connect initiate packets. Creates a standard access list. Creates a DECnet access group. Provides access control to hello messages or routing information received on an interface. decnet out-routing-filter Provides access control to routing information being sent out on an interface. show decnet interface Displays the global DECnet status and configuration for all interfaces.
Command
Description
The optional argument source-object consists of the following string:
src [{eq | neq | gt | lt} object-number] [exp regular-expression] [uic [group, user]]The optional argument destination-object consists of the following string:
dst [{eq | neq | gt | lt} object-number] [exp regular-expression] [uic [group, user]]The optional argument identification consists of the following string:
[id regular-expression] [password regular-expression] [account regular-expression]
Syntax Description
access-list-number Integer you choose between 300 and 399 that uniquely identifies the access list. permit Permits access when there is an address match. deny Denies access when there is an address match. source Source address. DECnet addresses are written in the form area.node. For example, 50.4 is node 4 in area 50. All addresses are in decimal. source-mask Mask to be applied to the address of the source node. All masks are in decimal. destination (Optional) Destination node's DECnet address in decimal format. DECnet addresses are written in the form area.node. For example, 50.4 is node 4 in area 50. All addresses are in decimal. destination-mask (Optional) Destination mask. DECnet addresses are written in the form area.node. For example, 50.4 is node 4 in area 50. All masks are in decimal. eq | neq Use either of these keywords: source-object (Optional) Contains the mandatory keyword src and one of the following optional keywords: destination-object (Optional) Contains the mandatory keyword dst and one of the following optional keywords: identification (Optional) Uses any of the following three keywords: any (Optional) Item matches if any of the specified parts do match the corresponding entries for source-object, destination-object, or identification.
Defaults
No access list is defined.
Command Modes
Global configuration
Command History
10.0 This command was introduced.
Release
Modification
Usage Guidelines
Depending upon the arguments you use, you can define access lists in three ways:
Table 20 lists the DECnet object numbers.
| Name | Number | Description |
|---|---|---|
FAL | 17 | File Access Listener |
HLD | 18 | Host Loader |
NML | 19 | Network Monitor Link/NICE |
MIRROR | 25 | Loopback mirror |
EVL | 26 | Event logger |
27 | ||
PHONE | 29 | Phone |
NOTES | 33 | VAX Notes |
CTERM | 42 | Terminal sessions |
DTR | 63 | DECnet Test Sender/Receiver |
Examples
The following example illustrates an access list for matching all connect packets for object number 27:
access-list 300 permit 0.0 63.1023 eq dst eq 27
The following example illustrates an access list for matching all connect packets except for the object number 17:
access-list 300 permit 0.0 63.1023 neq dst eq 17
The following example illustrates an access list for matching all connect packets where the access identification was SYSTEM:
access-list 300 permit 0.0 63.1023 eq id ^SYSTEM$
The following example illustrates an access list for matching all connect packets from area 1 to object number 27(27 = VAX/VMS Personal Utility or MAIL) where SYSTEM is the originating user:
access-list 300 permit 1.0 0.1023 eq src exp ^SYSTEM$ dst eq 27
The following example illustrates an access list for matching any connect packet and can be used at the end of a list to permit any packets not already matched:
access-list 300 permit 0.0 63.1023 eq any
Related Commands
access-list (DECnet extended) Creates an extended access list. Creates a standard access list. Creates a DECnet access group. Provides access control to hello messages or routing information received on an interface. decnet out-routing-filter Provides access control to routing information being sent out on an interface. show decnet interface Displays the global DECnet status and configuration for all interfaces.
Command
Description
Syntax Description
access-list-number Integer you choose between 300 and 399 that uniquely identifies the access list. permit Permits access when there is an address match. deny Denies access when there is an address match. source Source address. DECnet addresses are written in the form area.node. For example, 50.4 is node 4 in area 50. All addresses are in decimal. source-mask Mask to be applied to the address of the source node. Bits are set wherever the corresponding bits in the address should be ignored. All masks are in decimal.
Defaults
No access list is defined.
Command Modes
Global configuration
Command History
10.3 This command was introduced.
Release
Modification
Usage Guidelines
In contrast with IP masks, a DECnet mask specification of "all ones" is entered as the decimal value 1023. In IP, the equivalent is 255.
Examples
The following example sets up access list 300 to deny packets coming from node 4.51 and permit packets coming from 2.31:
access-list 300 deny 4.51 0.0 access-list 300 permit 2.31 0.0
Related Commands
Creates an extended access list. Creates an access list that filters connect initiate packets. Creates a DECnet access group. Provides access control to hello messages or routing information received on an interface. decnet out-routing-filter Provides access control to routing information being sent out on an interface. show decnet interface Displays the global DECnet status and configuration for all interfaces.
Command
Description
To delete all entries in the accounting database when DECnet accounting is enabled, use the clear decnet accounting command in EXEC mode.
clear decnet accounting [checkpoint]
Syntax Description
checkpoint (Optional) Clears the checkpoint database.
Command Modes
EXEC
Command History
11.2 This command was introduced.
Release
Modification
Usage Guidelines
Specifying the clear decnet accounting command without the checkpoint keyword copies the active database to the checkpoint database and clears the active database.
Any traffic that traverses the router after the clear decnet accounting command has been issued is saved in the active database. Accounting information in the checkpoint database at that time reflects traffic prior to the most recent clear decnet accounting command.
You can also delete all entries in both the active and the checkpoint databases by issuing the clear decnet accounting command twice in succession.
Examples
In the following example, the first display from the show decnet accounting command shows the active database before a clear command is issued. The clear decnet accounting command is issued and a second show display shows no accounting information in the active database. The display from the show decnet accounting checkpoint command shows the data collected in the active database prior to the clear decnet accounting command.
Router# show decnet accounting Source Destination Bytes Packets 2.329 37.4 153 6 5.7 7.8 326 4 27.100 27.107 145 5 7.8 5.7 152 12 27.107 27.100 500 5 37.4 2.329 78 4 Accounting data age is 12.41 Router# clear decnet accounting Router# show decnet accounting Source Destination Bytes Packets Accounting data age is 0 Router# show decnet accounting checkpoint Source Destination Bytes Packets 2.329 37.4 153 6 5.7 7.8 326 4 27.100 27.107 145 5 7.8 5.7 152 12 27.107 27.100 500 5 37.4 2.329 78 4 Accounting data age is 12.41
Related Commands
Enables DECnet accounting. Specifies the source and destination address pairs for which DECnet accounting information is kept. Sets the maximum number of accounting database entries. Sets the maximum number of transit entries that will be stored in the DECnet accounting database. show decnet accounting Displays the active accounting or checkpointed database.
Command
Description
Syntax Description
This command has no arguments or keywords.
Command Modes
EXEC
Command History
10.0 This command was introduced.
Release
Modification
Examples
The following example zeros all DECnet counters:
clear decnet counters
Related Commands
show decnet traffic Shows the DECnet traffic statistics (including datagrams sent, received, and forwarded).
Command
Description
Syntax Description
access-list-number Either a standard or extended DECnet access list. A standard DECnet access list applies to source addresses. The value (or values in the case of extended lists) can be in the range 300 to 399.
Defaults
No access group is defined.
Command Modes
Interface configuration
Command History
10.0 This command was introduced.
Release
Modification
Examples
The following example applies access list 389 to Ethernet interface 1:
interface ethernet 1 decnet access-group 389
Related Commands
Creates a standard access list. show decnet interface Displays the global DECnet status and configuration for all interfaces.
Command
Description
To enable DECnet accounting, use the decnet accounting command in interface configuration mode. To disable DECnet accounting, use the no form of this command.
decnet accountingSyntax Description
This command has no arguments or keywords.
Defaults
Disabled
Command Modes
Interface configuration
Command History
11.2 F This command was introduced.
Release
Modification
Usage Guidelines
The Cisco IOS software maintains two accounting databases: an active database and a checkpoint database. The active database contains accounting data tracked until the database is cleared. When the active database is cleared, its contents are copied to the checkpoint database. Using these two databases together allows you to monitor both current traffic and traffic which has previously traversed the router.
DECnet accounting statistics will be accurate, even if DECnet fast switching is enabled, or if DECnet access lists are being used.
Enabling DECnet accounting significantly decreases the performance of a fast-switched interface.
DECnet accounting is disabled if autonomous or SSE switching is enabled.
Examples
This example shows DECnet accounting enabled on a serial interface 0:
interface serial 0 decnet accounting
Related Commands
Deletes all entries in the accounting database when DECnet accounting is enabled. Specifies the source and destination address pairs for which DECnet accounting information is kept. Sets the maximum number of accounting database entries. Sets the maximum number of transit entries that will be stored in the DECnet accounting database. show decnet accounting Displays the active accounting or checkpointed database.
Command
Description
To specify the source and destination address pairs for which DECnet accounting information is kept, use the decnet accounting list command in global configuration mode. DECnet accounting tracks all traffic that traverses the router between the source and destination address pairs specified with this command. To remove the accounting filter, use the no form of this command.
decnet accounting list src-dec-address dest-dec-address
Syntax Description
src-dec-address DECnet address for the source. The address is in the form area.node, for example, 5.3. dest-dec-address DECnet address for the destination. The address is in the form area.node, for example, 5.3. all Disables DECnet accounting for all source and destination address pairs specified previously with the decnet accounting list command.
Defaults
No filters are predefined.
Command Modes
Global configuration
Command History
11.2 F This command was introduced.
Release
Modification
Usage Guidelines
The source and destination addresses of each DECnet packet are paired to create an entry in the database. When DECnet traffic traverses the router and a match is found, accounting information about the DECnet packet is entered into the accounting database. If DECnet accounting is enabled on an interface, but no accounting list is specified, the transit parameter does not come into play. DECnet accounting will track all traffic through the interface, up to the accounting threshold limit. All traffic up to the threshold limit is collected and added to the aggregate value for all DECnet traffic passing through the router.
Use the no decnet accounting list all to delete the entire entry list.
Examples
The following example adds DECnet host pair 5.37 and 6.126 to the list of networks for which accounting information is kept:
decnet accounting list 5.37 6.126
Related Commands
Deletes all entries in the accounting database when DECnet accounting is enabled. Enables DECnet accounting. Sets the maximum number of accounting database entries. Sets the maximum number of transit entries that will be stored in the DECnet accounting database. show decnet accounting Displays the active accounting or checkpointed database.
Command
Description
To set the maximum number of accounting database entries, use the decnet accounting threshold command in global configuration mode. To restore the default, use the no form of this command.
decnet accounting threshold threshold
Syntax Description
threshold Maximum number of entries (source and destination address pairs) that the Cisco IOS software can accumulate.
Defaults
512 entries
Command Modes
Global configuration
Command History
11.2 F This command was introduced.
Release
Modification
Usage Guidelines
The accounting threshold defines the maximum number of entries (source and destination address pairs) that the software accumulates. The threshold is designed to prevent DECnet accounting from consuming all available free memory. This level of memory consumption could occur in a router that is switching traffic for many hosts. To determine whether overflows have occurred, use the show decnet accounting EXEC command.
Examples
The following example sets the DECnet accounting database threshold to 256 entries:
decnet accounting threshold 256
Related Commands
Deletes all entries in the accounting database when DECnet accounting is enabled. Enables DECnet accounting. Specifies the source and destination address pairs for which DECnet accounting information is kept. Sets the maximum number of transit entries that will be stored in the DECnet accounting database. show decnet accounting Displays the active accounting or checkpointed database.
Command
Description
To set the maximum number of transit entries that will be stored in the DECnet accounting database, use the decnet accounting transits command in global configuration mode. To disable this function, use the no form of this command.
decnet accounting transits count
Syntax Description
count Number of transit entries that will be stored in the DECnet accounting database.
Defaults
0 entries
Command Modes
Global configuration
Command History
11.2 F This command was introduced.
Release
Modification
Usage Guidelines
Transit entries are those that do not match any of the source and destination address pair filters specified by decnet accounting list global configuration commands. If an accounting list is not defined, DECnet accounting will track all traffic through the interface (all transit entries) up to the accounting threshold limit.
To maintain accurate accounting totals, the Cisco IOS software maintains two accounting databases: an active database and a checkpoint database.
Examples
The following example specifies a maximum of 100 transit records to be stored in the DECnet accounting database:
decnet accounting transits 100
Related Commands
Deletes all entries in the accounting database when DECnet accounting is enabled. Specifies the source and destination address pairs for which DECnet accounting information is kept. Sets the maximum number of accounting database entries. show decnet accounting Displays the active accounting or checkpointed database.
Command
Description
To configure border routers to propagate Phase IV areas through an OSI backbone, use the decnet advertise command in global configuration mode. To disable this function, use the no form of this command.
decnet advertise decnet-area hops cost
Syntax Description
decnet-area Phase IV area that you want propagated. hops Hop count to be associated with the route being advertised. Default is 0. cost Cost to be associated with the route being advertised. Default is 0.
Defaults
Disabled
Command Modes
Global configuration
Command History
10.0 This command was introduced.
Release
Modification
Usage Guidelines
The output from the show decnet route EXEC command shows the cost and hop count for routes.
The decnet advertise command is used by border routers for propagating Phase IV areas through an OSI backbone.
The decnet advertise command and the clns route nsap-prefix discard command work together. When a router has DECnet Phase IV/V conversion enabled, any packet with the specified Connectionless Network Service (CLNS) Network Service Access Point (NSAP) prefix will cause CLNS to behave as if no route were found. That router then looks up the route to the border router that is advertising the Phase IV route. In turn, the router that is advertising the DECnet Phase IV route converts the packet to Phase V and sends it through the OSI cloud to the border router that is advertising the CLNS discard static route. After the packet gets to the border router, it is converted back to Phase IV.
The CLNS discard routes are created dynamically when the advertised adjacencies are propagated through the CLNS cloud. When a DECnet interface is disabled, the adjacencies are lost and the CLNS discard route is deleted. The DECnet area routing states are displayed in the output from the show decnet route EXEC command.
Examples
The following example shows a partial use of the decnet advertise command:
decnet conversion 49 decnet advertise 4 clns route 49.0001 discard
Related Commands
clns route discard Explicitly tells a router to discard packets with NSAP addresses that match the specified nsap-prefix. show decnet route Displays the DECnet routing table.
Command
Description
Syntax Description
network-number (Optional) Network number from 0 to 3. Specified when using Address Translation Gateway (ATG). If not specified, the default is network 0. value Maximum cost for a route to a distant area that the Cisco IOS software may consider usable; the software treats as unreachable any route with a cost greater than the value you specify. A valid range for cost is 1 to 1022. This parameter is only valid for area routers. The default is 1022.
Defaults
network-number: 0
value: 1022
Command Modes
Global configuration
Command History
10.0 This command was introduced.
Release
Modification
Usage Guidelines
Be sure that you have used the decnet node-type area global configuration command before using this command.
Examples
The following example specifies the node type as area and sets the maximum cost to 500. Any route with a cost exceeding 500 is considered unreachable by this router.
decnet node-type area decnet area-max-cost 500
Related Commands
Sets the maximum hop count value for interarea routing. Specifies the node type. show decnet interface Displays the global DECnet status and configuration for all interfaces.
Command
Description
To set the maximum hop count value for interarea routing, use the decnet area-max-hops command in global configuration mode.
decnet [network-number] area-max-hops value
Syntax Description
network-number (Optional) Network number in the range 0 to 3. Specified when using ATG. If not specified, the default is network 0. value Maximum number of hops for a usable route to a distant area. The Cisco IOS software treats as unreachable any route with a count greater than the value you specify. A valid range for the hop count is 1 to 30. The default is 30 hops.
Defaults
30 hops
Command Modes
Global configuration
Command History
10.0 This command was introduced.
Release
Modification
Usage Guidelines
This command is only valid for area routers. Be sure that you have issued the decnet node-type area global configuration command before using this command.
Examples
The following example sets the router to be a Level 2 router, then sets a maximum hop count of 21:
decnet node-type area decnet area-max-hops 21
Related Commands
Sets the maximum cost specification value for interarea routing. Specifies the node type. show decnet interface Displays the global DECnet status and configuration for all interfaces.
Command
Description
Syntax Description
number Number of packets that are allowed in the output queue before the system sets the congestion experience bit. This value is an integer between 0 and 0x7fff. The value zero prevents this bit from being set. Only relatively small integers are reasonable. The default is 1 packet.
Defaults
1 packet
Command Modes
Interface configuration
Command History
10.0 This command was introduced.
Release
Modification
Usage Guidelines
If a router configured for DECnet experiences congestion, it sets the congestion-experienced bit. A number value of zero or the no form of the command prevents this bit from being set.
Examples
The following example sets the congestion threshold to 10:
interface ethernet 0 decnet congestion-threshold 10
To allow Phase IV routers (running Cisco Release 9.1 or higher) to run in a Phase V network and vice versa, enable conversion with the decnet conversion command in global configuration mode. To disable conversion, use the no form of this command.
decnet conversion nsap-prefix
Syntax Description
nsap-prefix Value used for the IDP field when constructing NSAPs from a Phase IV address.
Defaults
Disabled
Command Modes
Global configuration
Command History
10.0 This command was introduced.
Release
Modification
Usage Guidelines
To enable DECnet conversion, you must configure both DECnet and ISO CLNS on your router.
DECnet Phase V is OSI-compatible and conforms to the ISO 8473 (CLNP/CLNS) and
ISO 9542 (ES-IS) standards. Digital has defined algorithms for mapping a subset of the Phase V address space onto the Phase IV address space and for converting Phase IV and Phase V packets back and forth. This allows a network administrator to support both Phase IV hosts in Phase V networks and Phase V hosts in Phase IV networks.
Cisco's implementation differs from Digital's in how reachability information is advertised. Cisco's implementation allows you to add Phase V support without modifying your existing Phase IV support. It also delays converting packets from Phase IV to Phase V, while Digital's implementation converts as soon as possible.
It is essential that the area you specify in the decnet routing global configuration command is the same as the local area you specified with the net router configuration command for the CLNS network.
Be sure that the area you specify in the decnet conversion command is the same as the area you specified for the CLNS network. Also note that the DECnet area is specified in decimal, and the CLNS area is specified in hexadecimal.
The decnet routing command is specified with a decimal address, while the net command address is specified in hexadecimal. In addition, the nsap-prefix specified on the decnet conversion command must match one of the NETs for this router.
The following guidelines apply:
Examples
The following example enables DECnet conversion on a router with the area tag xy and Phase IV address 20.401 using an ISO IGRP router:
clns routing decnet routing 20.401 decnet max-address 600 ! router iso-igrp xy net 47.0004.004d.0014.aa00.0400.9151.00 ! decnet conversion 47.0004.004d ! interface ethernet 0 decnet cost 4 clns router iso-igrp xy
Related Commands
net Configures an IS-IS NET for the routing process. show decnet interface Displays the global DECnet status and configuration for all interfaces. show decnet route Displays the DECnet routing table.
Command
Description
To set a cost value for an interface, use the decnet cost command in interface configuration mode. To disable DECnet routing for an interface, use the no form of this command.
decnet cost cost-value
Syntax Description
cost-value Integer from 1 to 63. There is no default cost for an interface, although a suggested cost for FDDI is 1, for Ethernet is 4, and for serial links is greater than 10.
Defaults
Disabled
Command Modes
Interface configuration
Command History
10.0 This command was introduced.
Release
Modification
Usage Guidelines
The decnet cost command is required for all interfaces on which DECnet routing is configured.
After DECnet routing has been enabled, you must assign a cost to each interface over which you want DECnet to run. Assigning a cost in effect enables DECnet routing for an interface. Most DECnet installations have an individualized routing strategy for using costs. Therefore, check the routing strategy used at your installation to ensure that costs you specify are consistent with those set for other hosts on the network.
Examples
The following example establishes a DECnet routing process for a router and sets the router's DECnet address to 21.456, then sets a cost of 4 for the Ethernet interface 0:
decnet routing 21.456 interface ethernet 0 decnet cost 4
Related Commands
Provides DECnet encapsulation over Token Ring. Specifies the node type. decnet routing Enables DECnet routing. show decnet interface Displays the global DECnet status and configuration for all interfaces. show decnet route Displays the DECnet routing table.
Command
Description
To provide DECnet encapsulation over Token Ring, use the decnet encapsulation command in interface configuration mode.
decnet encapsulation {pre-dec | dec}
Syntax Description
pre-dec Configures routers for operation on the same Token Ring with routers running software versions prior to Cisco IOS Release 9.1. In this mode, Cisco routers cannot communicate with non-Cisco equipment. Referred to as Cisco-style encapsulation. dec Provides encapsulation that is compatible with other Digital equipment. All Cisco routers must be running Cisco IOS Release 9.1 or later.
Defaults
Encapsulation is compatible with other Digital equipment.
Command Modes
Interface configuration
Command History
10.0 This command was introduced.
Release
Modification
Usage Guidelines
If you have both Release 9.0 and 9.1 routers in the same network, you must use the pre-dec encapsulation type on the 9.1 routers.
|
Note You must first enable DECnet routing on the selected Token Ring interface before you can configure the DECnet encapsulation mode. |
Examples
The following example sets Cisco-style encapsulation for DECnet routing, which means that Cisco and Digital equipment will not interoperate over Token Ring:
interface tokenring 0 decnet encapsulation pre-dec decnet cost 4
Related Commands
Sets a cost value for an interface. show decnet interface Displays the global DECnet status and configuration for all interfaces.
Command
Description
To change the interval for sending broadcast hello messages, use the decnet hello-timer command in interface configuration mode. To restore the default value, use the no form of this command.
decnet hello-timer seconds
Syntax Description
seconds Interval at which the Cisco IOS software sends hello messages. It can be a decimal number in the range 1 to 8191 seconds. The default is 15 seconds.
Defaults
15 seconds
Command Modes
Interface configuration
Command History
10.0 This command was introduced.
Release
Modification
Usage Guidelines
The Cisco IOS software broadcasts hello messages on all interfaces with DECnet enabled. Other hosts on the network use the hello messages to identify the hosts with which they can communicate directly. On extremely slow serial lines, you may want to increase the default value to reduce overhead on the line.
Examples
The following example increases the hello interval to 2 minutes (120 seconds) on serial interface 1:
interface serial 1 decnet hello-timer 120
Related Commands
show decnet interface Displays the global DECnet status and configuration for all interfaces.
Command
Description
To associate a name-to-DECnet address mapping, use the decnet host command in global configuration mode. To disable name mapping, use the no form of this command.
decnet host name decnet-address
Syntax Description
name A name you choose that uniquely identifies this DECnet address. decnet-address Source address. DECnet addresses are written in the form area.node. For example, 50.4 is node 4 in area 50. All addresses are in decimal.
Defaults
No name is defined.
Command Modes
Global configuration
Command History
10.3 This command was introduced.
Release
Modification
Usage Guidelines
The assigned name is displayed, where applicable, in show decnet route and show hosts EXEC command output.
The name can also be used with the ping decnet command.
Examples
The following example defines name-to-DECnet address mapping:
decnet host cisco1 3.33
Related Commands
show decnet Displays the global DECnet parameters. show decnet route Displays the DECnet routing table. show hosts Displays the default domain name, the style of name lookup service, a list of name server hosts, and the cached list of host names and addresses.
Command
Description
Syntax Description
access-list-number Standard DECnet access list. This list applies to source addresses. The value can be in the range 300 to 399.
Defaults
No access control is defined.
Command Modes
Interface configuration
Command History
10.0 This command was introduced.
Release
Modification
Examples
The following example sets up Ethernet interface 0 with a DECnet in-routing filter of 321, which means that any hello messages sent from addresses that are denied in list 321 are ignored. Additionally, all node addresses listed in received routing messages on this interface are checked against the access list, and only routes passing the filter are considered usable.
interface ethernet 0 decnet in-routing-filter 321
Related Commands
Creates a standard access list. decnet out-routing-filter Provides access control to routing information being sent out on an interface. show decnet interface Displays the global DECnet status and configuration for all interfaces.
Command
Description
Syntax Description
first-network DECnet network numbers in the range 0 to 3. virtual-address Numeric DECnet address (10.5, for example). second-network DECnet network number you map to; DECnet numbers range 0 to 3. real-address Numeric DECnet address (10.5, for example).
Defaults
No address translation is defined.
Command Modes
Global configuration
Command History
10.0 This command was introduced.
Release
Modification
Usage Guidelines
Keep the following limitations in mind when configuring the address translation gateway (ATG):
As an additional feature and security caution, DECnet "Poor Man's Routing" can be used between nodes outside of the translation map as long as those nodes have access to nodes that are in the map, so that a user on node B could issue the following VMS command:
$ dir A::D::E::
|
Note Cisco does not support "Poor Man's Routing" directly; the intermediate nodes must be VMS systems with "Poor Man's Routing" enabled in file-access language. |
Examples
In the following example, packets in network 0 sent to address 19.5 will be routed to network 1, and the destination address will be translated to 50.1. Packets sent to address 47.1 in network 1 will be routed to network 0 as 19.1.
decnet 0 map 19.5 1 50.1 decnet 1 map 47.1 0 19.1
Related Commands
show decnet map Displays the address mapping information used by the DECnet Address Translation Gateway.
Command
Description
To configure the Cisco IOS software with a maximum number of node addresses, use the decnet max-address command in global configuration mode.
decnet [network-number] max-address value
Syntax Description
network-number (Optional) Network number in the range 0 to 3. Specified when using ATG. If not specified, the default is network 0. value A number less than or equal to 1023 that represents the maximum address possible on the network. In general, all routers on the network should use the same value for this argument. The default is 1023.
Defaults
1023 node addresses
Command Modes
Global configuration
Command History
10.0 This command was introduced.
Release
Modification
Usage Guidelines
DECnet routers do not have the concept of aging out a route. Therefore, all possible areas or nodes must be advertised as unreachable if they cannot be reached. Since it is best to keep routing updates small, you must indicate the default maximum possible node and area numbers that can exist in the network.
Examples
The following example configures a small network to a maximum address value of 300:
decnet max-address 300
Related Commands
Sets the largest number of areas that the Cisco IOS software can handle in its routing table.
Command
Description
Syntax Description
network-number (Optional) Network number in the range 0 to 3. Specified when using ATG. If not specified, the default is network 0. area-number Area number from 1 to 63. Like the decnet max-address global configuration command value, this argument controls the sizes of internal routing tables and of messages sent to other nodes. All routers on the network should use the same maximum address value. The default is 63.
Defaults
63 areas
Command Modes
Global configuration
Command History
10.0 This command was introduced.
Release
Modification
Examples
In the following example, the largest area to be stored in the routing table is 45:
decnet max-area 45
Related Commands
Configures the Cisco IOS software with a maximum number of node addresses. show decnet interface Displays the global DECnet status and configuration for all interfaces.
Command
Description
To set the maximum cost specification for intra-area routing, use the decnet max-cost command in global configuration mode.
decnet [network-number] max-cost cost
Syntax Description
network-number (Optional) Network number in the range 0 to 3. Specified when using ATG. If not specified, the default is network 0. cost Cost from 1 to 1022. The default is 1022.
Defaults
1022
Command Modes
Global configuration
Command History
10.0 This command was introduced.
Release
Modification
Usage Guidelines
The Cisco IOS software ignores routes within its local area that have a cost greater than the value you specify.
Examples
The following example specifies the node type as a Level 1 router and sets the maximum cost to 335. Any route whose cost exceeds 335 is considered unreachable by this router.
decnet node-type routing-iv decnet max-cost 335
Related Commands
Sets the maximum hop count specification value for intra-area routing. Defines the maximum number of equal-cost paths to a destination that the Cisco IOS software keeps in its routing table. Specifies the node type. decnet path-split-mode Specifies how the Cisco IOS software splits the routable packets between equal-cost paths. show decnet interface Displays the global DECnet status and configuration for all interfaces.
Command
Description
To set the maximum hop count specification value for intra-area routing, use the decnet max-hops command in global configuration mode.
decnet [network-number] max-hops hop-count
Syntax Description
network-number (Optional) Network number in the range 0 to 3. Specified when using ATG. If not specified, the default is network 0. hop-count Hop count from 1 to 30. The Cisco IOS software ignores routes that have a hop count greater than the corresponding value of this parameter. The default is 30 hops.
Defaults
30 hops
Command Modes
Global configuration
Command History
10.0 This command was introduced.
Release
Modification
Examples
The following example sets the router to be a Level 1 router, then sets a maximum hop count of 2:
decnet node-type routing-iv decnet max-hops 2
Related Commands
Sets the maximum cost specification for intra-area routing. Defines the maximum number of equal-cost paths to a destination that the Cisco IOS software keeps in its routing table. Specifies the node type.
Command
Description
To define the maximum number of equal-cost paths to a destination that the Cisco IOS software keeps in its routing table, use the decnet max-paths command in global configuration mode.
decnet [network-number] max-paths value
Syntax Description
network-number (Optional) Network number in the range 0 to 3. Specified when using ATG. If not specified, the default is network 0. value Decimal number equal to the maximum number of equal-cost paths the software will save. The valid range is 1 to 31. The default is 1.
Defaults
1 equal-cost path
Command Modes
Global configuration
Command History
10.0 This command was introduced.
Release
Modification
Usage Guidelines
Limiting the number of equal-cost paths can save memory on routers with limited memory or very large configurations. Additionally, in networks with a large number of multiple paths and end-systems with limited ability to cache out-of-sequence packets, performance may suffer when traffic is split between many paths.
Limiting the size of the routing table does not affect your routers' ability to recover from network failures transparently, provided that you do not make the maximum number of paths too small. If more than the specified number of equal-cost paths exist, and one of those paths suddenly becomes unusable, the software will discover an additional path from the paths it has been ignoring.
Examples
In the following example, the software will save no more than three equal-cost paths:
decnet max-paths 3
Related Commands
Sets the maximum cost specification for intra-area routing. Sets the maximum hop count specification value for intra-area routing. decnet path-split-mode Specifies how the Cisco IOS software splits the routable packets between equal-cost paths. show decnet interface Displays the global DECnet status and configuration for all interfaces. show decnet route Displays the DECnet routing table.
Command
Description
To set the limit on the number of times a packet can pass through a router, use the decnet max-visits command in global configuration mode.
decnet [network-number] max-visits value
Syntax Description
network-number (Optional) Network number in the range 0 to 3. Specified when using ATG. If not specified, the default is network 0. value Number of times a packet can pass through a router. It can be a decimal number in the range 1 to 63. If a packet exceeds value, the Cisco IOS software discards the packet. Digital recommends that the value of the max-visits parameter be at least twice that of the max-hops parameter, to allow packets to still reach their destinations when routes are changing. The default is 63 times.
Defaults
63 times
Command Modes
Global configuration
Command History
10.0 This command was introduced.
Release
Modification
Examples
The following example of intra-area routing configuration specifies Level 1 routing, a maximum hop count of 28, and maximum number of visits of 62 (which is more than twice 28):
decnet node-type routing-iv decnet max-hops 28 decnet max-visits 62
Related Commands
Sets the maximum hop count specification value for intra-area routing. show decnet interface Displays the global DECnet status and configuration for all interfaces. show decnet traffic Shows the DECnet traffic statistics (including datagrams sent, received, and forwarded).
Command
Description
To specify a mapping between DECnet multicast addresses and Token Ring functional addresses, other than the default mapping, use the decnet multicast-map command in interface configuration mode. To delete the specified information, use the no form of this command.
decnet multicast-map multicast-address-type functional-address
Syntax Description
multicast-address-type Type of multicast address that is used. The following are valid values for the argument: functional-address Functional MAC address to which this multicast ID maps; in the form of "c000.xxxx.yyyy."
Defaults
Enabled, with the default mapping listed in Table 21.
Command Modes
Interface configuration
Command History
10.0 This command was introduced.
Release
Modification
Usage Guidelines
This command is valid for Token Ring interfaces only. The command will reject a functional address that does not start with "C000" or "c000."
Routing multicasts and end node multicasts must be on different functional addresses. Table 21 shows the default mapping of DECnet multicast address types to token ring functional addresses.
| DECnet Multicast Address Type | Token Ring Functional Address |
|---|---|
L1 router | C000.1000.0000 |
End node | C000.0800.0000 |
DECnet Phase IV-Prime router | C000.1000.0000 |
Examples
The following example configures Token Ring interface 1 for multicasts of all Phase IV end nodes and the multicast ID is configured to map to MAC address c000.2222.3333:
interface tokenring 1 decnet multicast-map iv-all-endnodes c000.2222.3333
To specify the node type, use the decnet node-type command in global configuration mode.
decnet [network-number] node-type {area | routing-iv}
Syntax Description
network-number (Optional) Network number in the range 0 to 3. Specified when using ATG. If not specified, the default is network 0. area Router participates in the DECnet routing protocol with other area routers, as described in the Digital documentation, and routes packets from and to routers in other areas. This is sometimes referred to as Level 2 (or interarea) routing. An area router does not just handle interarea routing, it also acts as an intra-area or Level 1 router in its own area. routing-iv Router acts as an intra-area (standard DECnet Phase IV, Level 1 router) and ignores Level 2 routing packets. In this mode, it routes packets destined for other areas to a designated interarea router, exchanging packets with other end nodes and routers in the same area.
Defaults
No node type is specified.
Command Modes
Global configuration
Command History
10.0 This command was introduced.
Release
Modification
Examples
In the following example, the router node type is specified as area, or Level 2:
decnet node-type area
Related Commands
Sets a cost value for an interface. decnet routing Enables DECnet routing. show decnet interface Displays the global DECnet status and configuration for all interfaces.
Command
Description
Posted: Fri Mar 17 08:18:12 PST 2000
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