Packet-over-SONET Interface Commands on Cisco IOS XR Software
This module describes the Cisco IOS XR commands used to configure, monitor, and troubleshoot Packet-over-SONET/SDH (POS).
POS provides a method for efficiently carrying data packets in SONET or Synchronous Digital Hierarchy (SDH) frames. High-bandwidth capacity and efficient link utilization are characteristics that make POS largely preferred for building the core of data networks. POS uses PPP in High-Level Data Link Control (HDLC)-like framing for data encapsulation at Layer 2 (data link) of the Open System Interconnection (OSI) stack. This method provides efficient packet delineation and error control.
In addition to high-bandwidth efficiency, POS offers secure and reliable transmission for data. Reliable data transfer depends on timing integrity.
The real-time POS functionality is performed in hardware, according to the hardware configuration setup. Configured hardware events are detected by the framer application-specific integrated circuits (ASICs) and the control is passed to the software. The generic POS driver is responsible for providing a mechanism to configure the hardware on a per-interface basis, to handle interface state transitions, and to collect POS-related statistics.
crc (POS)
To set the length of the cyclic redundancy check (CRC) on a Packet-over-SONET/SDH (POS) interface, use the crc command in POS configuration mode. To return the CRC setting on a POS interface to the 32-bit default setting, use the no form of this command.
crc {16 | 32}
no crc {16 | 32}
Syntax Description
16 |
Sets 16-bit CRC mode. |
32 |
Sets 32-bit CRC mode. The default is 32 bits. |
Defaults
The default CRC mode is 32 bits.
Command Modes
POS configuration
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1 router. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
CRC is an error-checking technique that uses a calculated numeric value to detect errors in transmitted data. The designators 16 and 32 indicate the length (in bits) of the frame check sequence (FCS). A CRC of 32 bits provides more powerful error detection, but adds overhead. Both the sender and receiver must use the same setting.
CRC-16, the most widely used error checking method throughout the United States and Europe, is used extensively with WANs. CRC-32 is specified by IEEE standard 802 and as an option by some point-to-point transmission standards. It is often used on Switched Multimegabit Data Service (SMDS) networks and LANs.
Examples
In the following example, the 32-bit CRC on POS interface 0/1/0/2 is enabled:
RP/0/RP0/CPU0:router(config)# interface POS 0/1/0/2
RP/0/RP0/CPU0:router(config-if)# POS
RP/0/RP0/CPU0:router(config-if-pos)# crc 32
Related Commands
|
|
transmit-delay |
Specifies a number of flag sequences to be inserted between the packets. |
encapsulation (POS)
To set the Layer 2 encapsulation of an interface, use the encapsulation command in interface configuration mode. To restore the system to the default encapsulation, use the no form of this command.
encapsulation {hdlc | ppp | frame-relay}
no encapsulation
Syntax Description
hdlc |
Enables Cisco High-Level Data Link Control (cHDLC) encapsulation on the interface. This is the default encapsulation type. |
ppp |
Enables Point-to-Point Protocol (PPP) encapsulation on the interface. |
frame-relay |
Enables Frame Relay encapsuation on the interface. |
Defaults
For Packet-over-SONET/SDH (POS) interfaces, the default encapsulation is HDLC.
Command Modes
Interface configuration
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1 router. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
Frame Relay encapsulation was supported on POS interfaces. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
|
|
hdlc |
read, write |
interface |
read, write |
Examples
In the following example, PPP encapsulation is set on POS interface 0/3/0/1:
RP/0/RP0/CPU0:router(config)# interface POS 0/3/0/1
RP/0/RP0/CPU0:router(config-if)# encapsulation ppp
Related Commands
interface pos
To enter interface configuration mode for a POS interface, use the interface pos command in global configuration mode. To delete a POS configuration, use the no form of this command.
interface POS interface-path-id[.subinterface [point-to-point]]
no interface POS interface-path-id[.subinterface [point-to-point]]
Syntax Description
interface-path-id [.subinterface] |
Physical interface or virtual interface followed by the optional subinterface path ID. Naming notation is interface-path-id.subinterface. The period in front of the subinterface value is required as part of the notation. For more information about the syntax for the router, use the question mark (?) online help function. |
point-to-point |
(Optional) Interface functions as one endpoint of a point-to-point link. |
Defaults
No default behavior or values
Command Modes
Global configuration
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1 router. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
For the interface-path-id argument, use the following guidelines:
•If specifying a physical interface, the naming notation is rack/slot/module/port. The slash between values is required as part of the notation. An explanation of each component of the naming notation is as follows:
–rack: Chassis number of the rack.
–slot: Physical slot number of the line card.
–module: Module number. A physical layer interface module (PLIM) is always 0.
–port: Physical port number of the interface.
•If specifying a virtual interface, the number range varies, depending on interface type.
Examples
The following example shows how to enter interface configuration mode for a POS interface:
RP/0/RP0/CPU0:router(config)# interface pos 0/1/0/0
RP/0/RP0/CPU0:router(config-if)#
The following example shows how to create a subinterface on a POS interface in slot 1, subslot 1,
port 2 and enter subinterface configuration mode:
RP/0/0/CPU0:Router(config)# interface pos 0/1/1/2.1
RP/0/0/CPU0:Router(config-if)#
Related Commands
keepalive (POS)
To set the keepalive timer for a specific interface, use the keepalive command in interface configuration mode. To reset the keepalive timer to the default of 10 seconds, use the no form of this command.
keepalive {seconds | disable}
no keepalive
Syntax Description
seconds |
Number of seconds that define the keepalive interval. Range is from 0 through 32767 seconds. Default is 10 seconds. |
disable |
Turns off the keepalive timer. |
Defaults
seconds: 10
Command Modes
Interface configuration
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1 router. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
cHDLC keepalives require that the keepalive command is configured the same way on both routers. The two connected routers have no way of negotiating the keepalive value, because there is no way for the routers to tell each other what their configured values are. The keepalive value configured on each router (local and partner) sets the rate at which the Cisco IOS XR software sends packets. It also sets the rate at which the local end expects to receive incoming packets.
To set the keepalive value to the default value, use the keepalive command without specifying a value for the seconds argument.
If three keepalives are sent to the peer and no response is received from the peer, then the link makes the transition to the down state.
Examples
The following example shows how to configure keepalives for 3 seconds on POS interface 0/7/0/1:
RP/0/RP0/CPU0:router(config)# interface POS 0/7/0/1
RP/0/RP0/CPU0:router(config-if)# keepalive 3
pos
To access the POS configuration submode, use the pos command in interface configuration mode.
pos
Syntax Description
This command has no arguments or keywords.
Defaults
No default behavior or values
Command Modes
Interface configuration
Command History
|
|
Release 2.0 |
This command was introduced on the Cisco CRS-1 router. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
When you issue the pos command in interface configuration mode for a POS interface, the CLI prompt changes to "config-if-pos," indicating that you have entered POS configuration submode. In the following sample output, the question mark (?) online help function displays all the commands available under POS configuration submode:
RP/0/RP0/CPU0:router(config)# interface POS 0/1/0/2
RP/0/RP0/CPU0:router(config-if)# POS
RP/0/RP0/CPU0:router(config-if-pos)# ?
commit Commit the configuration changes to running
crc Set the CRC on a POS interface
describe Describe a command without taking real actions
exit Exit from this submode
no Negate a command or set its defaults
show Show contents of configuration
transmit-delay Set POS transmit delay on an interface
Examples
The following example shows how to access the POS configuration submode from the POS configuration mode:
RP/0/RP0/CPU0:router(config)# interface POS 0/1/0/2
RP/0/RP0/CPU0:router(config-if)# POS
RP/0/RP0/CPU0:router(config-if-pos)#
Related Commands
|
|
crc (POS) |
Sets the length of the CRC on a POS interface. |
transmit-delay |
Specifies a number of flag sequences to be inserted between the packets. |
show interfaces pos
To display information about a POS interface, use the show interfaces pos command in EXEC mode.
show interfaces pos [interface-path-id] [accounting [rates] | brief | description | detail | summary] [location node-id]
interface-path-id |
(Optional) Physical interface or virtual interface. Note Use the show interfaces command to see a list of all interfaces currently configured on the router. For more information about the syntax for the router, use the question mark (?) online help function. |
accounting |
(Optional) Displays accounting information for all POS interfaces on the router, for a specific POS interface instance, or for all POS interfaces on a specific node. |
rates |
(Optional) Displays interface accounting rates for all POS interfaces on the router, for a specific POS interface instance, or for all POS interfaces on a specific node. |
brief |
(Optional) Displays brief output for all POS interfaces on the router, for a specific POS interface instance, or for all POS interfaces on a specific node. |
description |
Displays descriptive output for all POS interfaces on the router, for a specific POS interface instance, or for all POS interfaces on a specific node. |
detail |
(Optional) Displays detailed output for all POS interfaces on the router, for a specific POS interface instance, or for all POS interfaces on a specific node. |
location node-id |
(Optional) Displays detailed POS information for the designated node. The node-id argument is entered in the rack/slot/module notation. |
summary |
(Optional) Displays summarized POS interface information. |
Defaults
Enter the show interfaces pos command without including any of the optional keywords or arguments to display detailed information about all POS interfaces configured on the router.
Command Modes
EXEC
Command History
|
|
Release 2.0 |
This command was first introduced on the Cisco CRS-1 router. |
Release 3.0 |
No modification. |
Release 3.2 |
This command was first supported on the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
For the interface-path-id argument, use the following guidelines:
•If specifying a physical interface, the naming notation is rack/slot/module/port. The slash between values is required as part of the notation. An explanation of each component of the naming notation is as follows:
–rack: Chassis number of the rack.
–slot: Physical slot number of the line card.
–module: Module number. A physical layer interface module (PLIM) is always 0.
–port: Physical port number of the interface.
•If specifying a virtual interface, the number range varies, depending on interface type.
Examples
The following example shows how to display summarized information for a POS interface on a specific node:
RP/0/RP0/CPU0:router# show interfaces pos summary location 0/1/CPU0
Interface Type Total UP Down Admin Down
-------------- ----- -- ---- ----------
Table 84 describes the significant fields shown in the display.
Table 84 show interfaces pos summary Field Descriptions
|
|
Intf Type |
Type of interface described in the display. |
Total |
Total number of configured interfaces of the specified type. |
Up |
Number of interfaces of the specified type that are in the "Up" state. |
Down |
Number of interfaces of the specified type that are in the "Down" state. |
Admin Down |
Number of interfaces of the specified type that are in the "Admin Down" state. |
The following example shows how to display brief information for a specific POS interface:
RP/0/RP0/CPU0:router# show interfaces pos 0/2/0/0 brief
Intf Intf LineP Encap MTU BW
Name State State Type (byte) (Kbps)
-------------------------------------------------------------------------------
PO0/2/0/0 admin-down admin-down HDLC 4474 2488320
Table 85 describes the significant fields shown in the display.
Table 85 show interfaces pos Field Descriptions
|
|
Intf Name |
Interface identifier, in the type*rack/slot/module/port notation. |
Intf State |
Indicates whether the interface is in the admin-up or admin down state. |
LineP State |
Line protocol state. |
Encap Type |
Encapsulation type for the specified interface. Can be HDLC or PPP. |
MTU (byte) |
Maximum transmission unit (MTU) value configured for the specified interface, in bytes. |
BW (Kbps) |
Bandwidth of the interface, in kbps. |
Related Commands
|
|
show controllers pos |
Displays information on the SONET controllers that are associated with Packet-over-SONET/SDH (POS) interfaces. |
show controllers sonet |
Displays information about the operational status of SONET layers. |
transmit-delay
To specify a number of flag sequences to be inserted between the packets, use the transmit-delay command in POS configuration mode. To restore the default, use the no form of this command.
transmit-delay microseconds
no transmit-delay microseconds
Syntax Description
microseconds |
Number of microseconds of minimum delay after sending a packet. Range is from 0 to 1023. Default is 0 (disabled). |
Defaults
microseconds = 0 (disabled)
Command Modes
POS configuration
Command History
|
|
Release 3.2 |
This command was introduced on the Cisco CRS-1 router and the Cisco XR 12000 Series Router. |
Release 3.3.0 |
No modification. |
Release 3.4.0 |
No modification. |
Release 3.5.0 |
No modification. |
Release 3.6.0 |
No modification. |
Release 3.7.0 |
No modification. |
Release 3.8.0 |
No modification. |
Usage Guidelines
To use this command, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide.
Examples
In the following example, a delay of 2 microseconds is specified on POS interface 0/1/0/2:
RP/0/0/CPU0:router# configure
RP/0/0/CPU0:router(config)# interface POS 0/1/0/2
RP/0/0/CPU0:router(config-if)# pos
RP/0/0/CPU0:router(config-if-pos)# transmit-delay 2
In the following example, the transmit delay on POS interface 0/1/0/2 is disabled:
RP/0/0/CPU0:router# configure
RP/0/0/CPU0:router(config)# interface POS 0/1/0/2
RP/0/0/CPU0:router(config-if)# pos
RP/0/0/CPU0:router(config-if-pos)# no transmit-delay
Related Commands
|
|
show interfaces |
Displays statistics for all interfaces configured on the router or on a specific node. |