Cable Modem
Steering on the Cisco cBR Series Converged Broadband Routers
First Published: July
13, 2016
The cable modem
steering feature helps to redirect or steer cable modems to multiple CMTS
routers. A configurable string is used to bond the cable modem to the proper
CMTS. Once the bonding is done, the CMTS can move the cable modem within itself
for load balancing.
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the Feature Information Table at the end of this document.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to http://tools.cisco.com/ITDIT/CFN/. An account on http://www.cisco.com/ is not required.
Prerequisites for
Cable Modem Steering
DOCSIS 3.0-defined
type, length, values (TLVs) are required to aid channel selection. All TLVs
encoded as general extension information in cable modem configuration files are
backward compatible with DOCSIS 1.1 and DOCSIS 2.0 cable modems.
 Note |
The hardware
components introduced in a given Cisco IOS Release are supported in all
subsequent releases unless otherwise specified.
|
Restrictions for
Cable Modem Steering
The Cable Modem
Steering feature has the following general restrictions:
- To restrict the cable
modem on the exact downstream on the target CMTS, the redirection must be
configured on the target CMTS.
- You must manually execute
the
clear
cable
modem
service-type command to clear the cable modem
service type identifier stored at the CMTS during registration.
- You must manually execute
the
clear
cable
modem
attribute-masks command to clear the cable modem
attribute masks stored at the CMTS during registration. These attribute masks
are used to restrict usage of upstream channels during ranging time.
- Cable modem steering
supports only upstream masks.
- Channel steering does not
take place when the cable modem fails in initial ranging.
- The cable modem will take
more time to come online when channel steering is deployed. The time taken is
proportional to the number of modems, and the downstreams and upstreams that
the cable modem can reach.
- A modem cannot be load
balanced to any upstream channel with attributes that conflict with attribute
masks of the modem.
- Do not configure to use
UCC in DOCSIS LBG.
Information About
Cable Modem Steering
Cable modem
steering allows you to redirect or steer the cable modems to one or more CMTS
routers using downstream frequency overrides. Once a cable modem registers on a
downstream on the proper CMTS router, the CMTS router can move the cable modem
to any location for load balancing.
The DOCSIS
3.0-compliant Service Type Identifier used as the configurable string in the
cable modem configuration file is backward-compatible with DOCSIS 1.1 and
DOCSIS 2.0 cable modems.
The CMTS router can
also impose restrictions on the number of channels a cable modem can use.
DOCSIS 3.0 defines several TLVs to aid the channel selection.
The following TLVs are used in cable modem steering:
- TLV 43.9 (Cable Modem
Attribute Masks) limits the set of channels the CMTS router can assign to the
cable modem by allowing or forbidding certain binary attributes. The cable
modem attribute masks have four sub-TLVs and cable modem steering makes use of
two sub-TLVs, which are listed below:
- TLV 43.9.3—Cable Modem
Upstream Required Attribute Mask (C.1.1.18.1.8.3 of
CM-SP-MULPIv3.0-I07-080215). It is a 32-bit mask representing the set of binary
upstream channel attributes required for the cable modem.
- TLV 43.9.4—Cable Modem
Upstream Forbidden Attribute Mask (C.1.1.18.1.8.4 of
CM-SP-MULPIv3.0-I07-080215). It is a 32-bit mask representing the set of binary
upstream channel attributes forbidden for the cable modem.
- TLV 43.11 is used for a
redirection action based on the service type identifier field. The cable modem
sends the TLV 43.11 in the REG-REQ MAC message. The DOCSIS 1.1 and DOCSIS 2.0
modems will also send this file ID when doing the registration.
- TLV43.1, defined as Policy
ID in DOCSIS 2.0 and DOCSIS 3.0, is parsed and stored in the cable modem during
registration. Before moving the cable modem during load balancing (LB), the
CMTS router checks whether the cable modem has a preconfigured policy with the
same Policy ID. If the policy does exist, the CMTS router disables LB for this
cable modem and moves to the next cable modem. If the policy does not exist on
the CMTS router, or the Policy ID is missing from the cable modem configuration
file, LB prohibition is not performed.
The following TLVs are supported in cable modem steering:
- TLV 43.11 (Service type
identifier) from section C.1.1.18.1.10 in CM-SP-MULPIv3.0-I07-080215.
- Cable modem attribute masks
(TLV 43.9) from C.1.1.18.1.8.3 and C.1.1.18.1.8.4 of
CM-SP-MULPIv3.0-I07-080215.
- TLV portion (43.1, Policy
ID) of REQ-REQ
- TLV 18--- Ranging Hold-off
Priority Field
- TLV 19---Channel Class ID
Upstream Channel
Descriptor TLV for Ranging Hold-off
The Upstream
Channel Descriptor (UCD) TLV for Ranging Hold-off feature, introduced in Cisco
IOS-XE 3.18.0SP Release, enables the Cisco cBR Series Converged Broadband
router to hold off a cable modem from initial ranging based on TLV 18 and 19
specified in the upstream channel descriptor (UCD) messages. The router can
hold off a cable modem from initial ranging only for 5 minutes. This default
value cannot be changed. This feature is supported with DOCSIS 2.0 and later
releases cable modems using upstream logical channels.
Ranging Class ID
The CMTS enables UCD TLV for ranging hold-off after detecting the TLVs from the cable modem registration request (REG-REQ) or multipart registration request (REG-REQ-MP), and saves these TLVs as a cable modem ranging class ID.
By default, DOCSIS load balance is supported for all cable modems with all types of ranging class IDs. In the event of DOCSIS load balance, a cable modem moves to the target upstream channel only if the ranging class ID matches with the upstream channel class ID.
Cable Modem Exclusion for DOCSIS Load Balance
You can exclude a cable modem or a group of cable modems from DOCSIS load balance based on their device type, MAC address, and Organizational Unique Identifier (OUI) using the cable load-balance exclude command in global configuration mode.
How to Configure Cable Modem Steering on the CMTS Router
This section describes the following required and optional procedures:
Configuring an
Upstream Channel Class ID
This
configuration is optional. A channel class ID must be configured for an
upstream logical channel if you want to configure UCD TLV ranging hold-off on
the CMTS router.
Procedure | Command or Action | Purpose |
---|
Step 1 | enable
Example:
Router> enable
|
Enables
privileged EXEC mode.
- Enter your password if
prompted.
|
Step 2 | configure
terminal
Example:
Router# configure terminal
|
Enters global
configuration mode.
|
Step 3 | controller
upstream-cable slot/subslot/controller-port-number
Example:
Router(config)# controller Upstream-Cable 3/0/0
|
Specifies the
cable interface and enters cable interface configuration mode. Arguments for
this command may vary depending on the CMTS router, line card, and Cisco IOS
software release. For details, see the
Cisco IOS CMTS Cable Command
Reference .
-
Slot— Slot where the interface card resides. The
valid range is from 0 to 3 and 6 to 9 on the Cisco cBR-8 router.
-
Subslot—Subslot where the interface card resides.
The valid value is 0 on the Cisco cBR-8 router.
-
controller-port-number—Controller port number. The
valid values are from 0 to 7 on the Cisco cBR-8 router.
|
Step 4 |
us-channel
us-channel-id
chan-class-id
id
Example:
Router(config-controller)# us-channel 3 chan-class-id ff
|
Configures
the channel class ID for an upstream logical channel.
- us-channel-id—Specifies the upstream channel id.
- id—Channel class ID for the logical upstream
channel in the hexadecimal format. The valid range is from 0 to ffffffff. The
default value is 0.
|
Step 5 | end
Example:
Router(config-controller)# end
|
Returns to
privileged EXEC mode.
|
Configuring an
Upstream Ranging Hold-off Priority Value
This configuration
is optional
Maximum time that
a cable modem can inhibit transmissions on an upstream channel in response to
its ranging class ID matching a bit value in the Ranging Hold-off Priority
field in the cable modem configuration file is 300 seconds (five minutes) per
DOCSIS 3.0 MAC
and Upper Layer Protocols Interface Specification . This default timer
value cannot be changed.
Procedure | Command or Action | Purpose |
---|
Step 1 | enable
Example:
Router> enable
|
Enables
privileged EXEC mode.
- Enter your password if
prompted.
|
Step 2 | configure
terminal
Example:
Router# configure terminal
|
Enters global
configuration mode.
|
Step 3 | controller
upstream-cable slot/subslot/controller-port-number
Example:
Router(config)# controller upstream-cable 3/0/0
|
Specifies the
cable interface and enters cable interface configuration mode. Arguments for
this command may vary depending on the CMTS router, line card, and Cisco IOS
software release. For details, see the
Cisco IOS CMTS Cable Command
Reference .
-
Slot—Slot
where the interface card resides. The valid range is from 0 to 3 and 6 to 9 on
the Cisco cBR-8 router.
-
Subslot—Subslot where the interface card resides.
The valid value is 0 on the Cisco cBR-8 router.
-
controller-port-number—Controller port number. The
valid values are from 0 to 7 on the Cisco cBR-8 router.
|
Step 4 | us-channel
us-channel-id
rng-holdoff
priority
Example:
Router(config-controller)# us-channel 3 rng-holdoff 1
|
Configures
the ranging hold-off priority value for an upstream logical channel.
- us-channel-id—Specifies the upstream channel id.
- rng-holdoff
priority—Specifies the ranging hold-off priority
value in the hexadecimal format. The valid range is from 0 to ffffffff. The
default value is 0.
|
Step 5 | end
Example:
Router(config-controller)# end
|
Returns to
privileged EXEC mode.
|
Verifying and Troubleshooting Cable Modem Steering
This section provides the verification and troubleshooting information:
Verifying an
Upstream Ranging Class ID Configuration
To verify an
upstream ranging class ID of a cable modem, use the
show
cable
modem command with the
verbose
keyword.
Following is a
sample output of the
show
cable
modem verbose command in Cisco IOS-XE Release 3.18.0SP:
Router# show cable modem 68b6.fcfe.22e5 verbose
MAC Address : 68b6.fcfe.22e5
IP Address : 192.168.0.8
IPv6 Address : 2001:DB8:10:1:9951:1972:33F9:9867
Dual IP : Y
Prim Sid : 8
Host Interface : C8/0/0/UB
MD-DS-SG / MD-US-SG : 1 / 2
MD-CM-SG : 0x5A0102
Primary Wideband Channel ID : 3073 (Wi8/0/0:0)
Primary Downstream : Mo8/0/0:0 (RfId : 2304)
Wideband Capable : Y
RCP Index : 3
RCP ID : 00 10 00 00 18
Downstream Channel DCID RF Channel : 45 8/0/0:0
Downstream Channel DCID RF Channel : 46 8/0/0:1
Downstream Channel DCID RF Channel : 47 8/0/0:2
Downstream Channel DCID RF Channel : 48 8/0/0:3
Downstream Channel DCID RF Channel : 49 8/0/0:4
Downstream Channel DCID RF Channel : 50 8/0/0:5
Downstream Channel DCID RF Channel : 51 8/0/0:6
Downstream Channel DCID RF Channel : 52 8/0/0:7
Downstream Channel DCID RF Channel : 53 8/0/0:8
Downstream Channel DCID RF Channel : 54 8/0/0:9
Downstream Channel DCID RF Channel : 55 8/0/0:10
Downstream Channel DCID RF Channel : 56 8/0/0:11
Downstream Channel DCID RF Channel : 57 8/0/0:12
Downstream Channel DCID RF Channel : 58 8/0/0:13
Downstream Channel DCID RF Channel : 59 8/0/0:14
Downstream Channel DCID RF Channel : 60 8/0/0:15
Downstream Channel DCID RF Channel : 61 8/0/0:16
Downstream Channel DCID RF Channel : 62 8/0/0:17
Downstream Channel DCID RF Channel : 63 8/0/0:18
Downstream Channel DCID RF Channel : 64 8/0/0:19
Downstream Channel DCID RF Channel : 65 8/0/0:20
Downstream Channel DCID RF Channel : 66 8/0/0:21
Downstream Channel DCID RF Channel : 67 8/0/0:22
Downstream Channel DCID RF Channel : 68 8/0/0:23
UDC Enabled : N
Extended Upstream Transmit Power : 61dB
Multi-Transmit Channel Mode : Y
Number of US in UBG : 8
Upstream Channel : US0 US1 US2 US3
Ranging Status : sta sta sta sta
Upstream SNR (dB) : 30.62 32.32 18.25 24.26
Upstream Data SNR (dB) : -- -- -- --
Received Power (dBmV) : 0.50 0.00 -0.50 -0.50
Reported Transmit Power (dBmV) : 30.75 30.75 29.25 29.25
Peak Transmit Power (dBmV) : 61.00 61.00 61.00 61.00
Phy Max Power (dBmV) : 48.00 48.00 48.00 48.00
Minimum Transmit Power (dBmV) : 21.00 21.00 21.00 21.00
Timing Offset (97.6 ns): 1800 1800 1800 1800
Initial Timing Offset : 1544 1544 1544 1544
Rng Timing Adj Moving Avg(0.381 ns): -1 0 -1 -1
Rng Timing Adj Lt Moving Avg : -7 0 -7 -7
Rng Timing Adj Minimum : -256 0 -256 -256
Rng Timing Adj Maximum : 65536 65536 65536 65536
Pre-EQ Good : 0 0 0 0
Pre-EQ Scaled : 0 0 0 0
Pre-EQ Impulse : 0 0 0 0
Pre-EQ Direct Loads : 0 0 0 0
Good Codewords rx : 1201 1262 833 656
Corrected Codewords rx : 0 0 169 117
Uncorrectable Codewords rx : 0 0 205 335
Phy Operating Mode : atdma* atdma* atdma* atdma*
Upstream Channel : US4 US5 US6 US7
Ranging Status : sta sta sta sta
Upstream SNR (dB) : 15.53 31.62 31.1 31.87
Upstream Data SNR (dB) : -- -- -- --
Received Power (dBmV) : 0.00 0.00 -0.50 0.50
Reported Transmit Power (dBmV) : 29.25 30.75 30.75 30.75
Peak Transmit Power (dBmV) : 61.00 61.00 61.00 61.00
Phy Max Power (dBmV) : 48.00 48.00 48.00 48.00
Minimum Transmit Power (dBmV) : 21.00 21.00 21.00 21.00
Timing Offset (97.6 ns): 1800 1800 1800 1800
Initial Timing Offset : 1544 1800 1544 1544
Rng Timing Adj Moving Avg(0.381 ns): -1 -1 46 0
Rng Timing Adj Lt Moving Avg : -7 -7 104 0
Rng Timing Adj Minimum : -256 -256 0 0
Rng Timing Adj Maximum : 65536 256 65536 65536
Pre-EQ Good : 0 0 0 0
Pre-EQ Scaled : 0 0 0 0
Pre-EQ Impulse : 0 0 0 0
Pre-EQ Direct Loads : 0 0 0 0
Good Codewords rx : 718 1328 1173 1252
Corrected Codewords rx : 110 0 0 0
Uncorrectable Codewords rx : 298 0 0 0
Phy Operating Mode : atdma* atdma* atdma* atdma*
sysDescr : DOCSIS 3.0 Cable Modem Router
Downstream Power : 7.40 dBmV (SNR = 43.30 dB)
MAC Version : DOC3.0
QoS Provisioned Mode : DOC1.1
Enable DOCSIS2.0 Mode : Y
Modem Status : {Modem= w-online, Security=disabled}
Capabilities : {Frag=N, Concat=N, PHS=Y}
Security Capabilities : {Priv=, EAE=Y, Key_len=}
L2VPN Capabilities : {L2VPN=Y, eSAFE=Y}
Sid/Said Limit : {Max US Sids=8, Max DS Saids=64}
Optional Filtering Support : {802.1P=N, 802.1Q=N, DUT=Y}
Transmit Equalizer Support : {Taps/Symbol= 1, Num of Taps= 24}
Number of CPE : 0(Max CPE = 16)
Number of CPE IPs : 0(Max CPE IPs = 16)
Number of CPE IPv6 : 0(Max CPE IPv6 = 16)
CFG Max-CPE : 16
Flaps : 19(Oct 11 04:00:25)
Errors : 0 CRCs, 0 HCSes
Stn Mtn Failures : 0 aborts, 12 exhausted
Total US Flows : 1(1 active)
Total DS Flows : 1(1 active)
Total US Data : 3294 packets, 577031 bytes
Total US Throughput : 0 bits/sec, 0 packets/sec
Total DS Data : 2263 packets, 200777 bytes
Total DS Throughput : 0 bits/sec, 0 packets/sec
LB group ID assigned (index) : 2153382146 (55810)
LB group ID in config file (index) : N/A (N/A)
LB policy ID : 0
LB policy ID in config file : 0
LB priority : 0
Tag :
Required DS Attribute Mask : 0x0
Forbidden DS Attribute Mask : 0x0
Required US Attribute Mask : 0x0
Forbidden US Attribute Mask : 0x0
Service Type ID :
Service Type ID in config file :
Ranging Class ID : 0x2
Active Classifiers : 0 (Max = NO LIMIT)
CM Upstream Filter Group : 0
CM Downstream Filter Group : 0
CPE Upstream Filter Group : 0
CPE Downstream Filter Group : 0
DSA/DSX messages : permit all
Voice Enabled : NO
DS Change Times : 0
Boolean Services : 2
Number of Multicast DSIDs Support : 63
MDF Capability Mode : 2
IGMP/MLD Version : MLDv2
FCType10 Forwarding Support : Y
Features Bitmask : 0x0
Total Time Online : 9h27m (9h27m since last counter reset)
CM Initialization Reason : BAD_DHCP_ACK
CFG Max IPv6 CPE Prefix : 16 (-1 used)
Additional
References
The following
sections provide references related to the Cable Modem Steering feature.
Standards and
RFCs
Standard
|
Title
|
CM-SP-MULPIv3.0-I07-080215
|
DOCSIS
3.0 MAC and Upper Layer Protocols Interface Specification
|
CM-SP-MULPIv3.0-I18-120329
|
DOCSIS
3.0 MAC and Upper Layer Protocols Interface Specification
|
CM-SP-RFI2.0-I13-080215
|
DOCSIS
2.0 Radio Frequency Interface Specification
|
Technical
Assistance
Description
|
Link
|
The
Cisco Support website provides extensive online resources, including
documentation and tools for troubleshooting and resolving technical issues with
Cisco products and technologies.
To
receive security and technical information about your products, you can
subscribe to various services, such as the Product Alert Tool (accessed from
Field Notices), the Cisco Technical Services Newsletter, and Really Simple
Syndication (RSS) Feeds.
Access
to most tools on the Cisco Support website requires a Cisco.com user ID and
password.
|
http://www.cisco.com/cisco/web/support/index.html
|
Feature
Information for Cable Modem Steering
Use Cisco Feature Navigator to find information about platform support and software image support. Cisco Feature Navigator enables you to determine which software images support a specific software release, feature set, or platform. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
 Note |
The table below lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.
|
Table 1 Feature
Information for Cable Modem Steering on the Cisco CMTS Routers
Feature
Name
|
Releases
|
Feature
Information
|
UCD TLV
for Ranging Hold-off
|
IOS-XE
3.18.0SP
|
The UCD
TLV for Ranging Hold-off feature enables the CMTS router to hold off a cable
modem from initial ranging.
The
following sections provide information about this feature:
The
following commands were introduced or modified:
- us-channel
chan-class-id
- us-channel
rng-holdoff
- show
cable
modem
verbose
|
Prerequisites for
Cable Modem Steering
DOCSIS 3.0-defined
type, length, values (TLVs) are required to aid channel selection. All TLVs
encoded as general extension information in cable modem configuration files are
backward compatible with DOCSIS 1.1 and DOCSIS 2.0 cable modems.
 Note |
The hardware
components introduced in a given Cisco IOS Release are supported in all
subsequent releases unless otherwise specified.
|
Restrictions for
Cable Modem Steering
The Cable Modem
Steering feature has the following general restrictions:
- To restrict the cable
modem on the exact downstream on the target CMTS, the redirection must be
configured on the target CMTS.
- You must manually execute
the
clear
cable
modem
service-type command to clear the cable modem
service type identifier stored at the CMTS during registration.
- You must manually execute
the
clear
cable
modem
attribute-masks command to clear the cable modem
attribute masks stored at the CMTS during registration. These attribute masks
are used to restrict usage of upstream channels during ranging time.
- Cable modem steering
supports only upstream masks.
- Channel steering does not
take place when the cable modem fails in initial ranging.
- The cable modem will take
more time to come online when channel steering is deployed. The time taken is
proportional to the number of modems, and the downstreams and upstreams that
the cable modem can reach.
- A modem cannot be load
balanced to any upstream channel with attributes that conflict with attribute
masks of the modem.
- Do not configure to use
UCC in DOCSIS LBG.
Information About
Cable Modem Steering
Cable modem
steering allows you to redirect or steer the cable modems to one or more CMTS
routers using downstream frequency overrides. Once a cable modem registers on a
downstream on the proper CMTS router, the CMTS router can move the cable modem
to any location for load balancing.
The DOCSIS
3.0-compliant Service Type Identifier used as the configurable string in the
cable modem configuration file is backward-compatible with DOCSIS 1.1 and
DOCSIS 2.0 cable modems.
The CMTS router can
also impose restrictions on the number of channels a cable modem can use.
DOCSIS 3.0 defines several TLVs to aid the channel selection.
The following TLVs are used in cable modem steering:
- TLV 43.9 (Cable Modem
Attribute Masks) limits the set of channels the CMTS router can assign to the
cable modem by allowing or forbidding certain binary attributes. The cable
modem attribute masks have four sub-TLVs and cable modem steering makes use of
two sub-TLVs, which are listed below:
- TLV 43.9.3—Cable Modem
Upstream Required Attribute Mask (C.1.1.18.1.8.3 of
CM-SP-MULPIv3.0-I07-080215). It is a 32-bit mask representing the set of binary
upstream channel attributes required for the cable modem.
- TLV 43.9.4—Cable Modem
Upstream Forbidden Attribute Mask (C.1.1.18.1.8.4 of
CM-SP-MULPIv3.0-I07-080215). It is a 32-bit mask representing the set of binary
upstream channel attributes forbidden for the cable modem.
- TLV 43.11 is used for a
redirection action based on the service type identifier field. The cable modem
sends the TLV 43.11 in the REG-REQ MAC message. The DOCSIS 1.1 and DOCSIS 2.0
modems will also send this file ID when doing the registration.
- TLV43.1, defined as Policy
ID in DOCSIS 2.0 and DOCSIS 3.0, is parsed and stored in the cable modem during
registration. Before moving the cable modem during load balancing (LB), the
CMTS router checks whether the cable modem has a preconfigured policy with the
same Policy ID. If the policy does exist, the CMTS router disables LB for this
cable modem and moves to the next cable modem. If the policy does not exist on
the CMTS router, or the Policy ID is missing from the cable modem configuration
file, LB prohibition is not performed.
The following TLVs are supported in cable modem steering:
- TLV 43.11 (Service type
identifier) from section C.1.1.18.1.10 in CM-SP-MULPIv3.0-I07-080215.
- Cable modem attribute masks
(TLV 43.9) from C.1.1.18.1.8.3 and C.1.1.18.1.8.4 of
CM-SP-MULPIv3.0-I07-080215.
- TLV portion (43.1, Policy
ID) of REQ-REQ
- TLV 18--- Ranging Hold-off
Priority Field
- TLV 19---Channel Class ID
Upstream Channel
Descriptor TLV for Ranging Hold-off
The Upstream
Channel Descriptor (UCD) TLV for Ranging Hold-off feature, introduced in Cisco
IOS-XE 3.18.0SP Release, enables the Cisco cBR Series Converged Broadband
router to hold off a cable modem from initial ranging based on TLV 18 and 19
specified in the upstream channel descriptor (UCD) messages. The router can
hold off a cable modem from initial ranging only for 5 minutes. This default
value cannot be changed. This feature is supported with DOCSIS 2.0 and later
releases cable modems using upstream logical channels.
Ranging Class ID
The CMTS enables UCD TLV for ranging hold-off after detecting the TLVs from the cable modem registration request (REG-REQ) or multipart registration request (REG-REQ-MP), and saves these TLVs as a cable modem ranging class ID.
By default, DOCSIS load balance is supported for all cable modems with all types of ranging class IDs. In the event of DOCSIS load balance, a cable modem moves to the target upstream channel only if the ranging class ID matches with the upstream channel class ID.
Cable Modem Exclusion for DOCSIS Load Balance
You can exclude a cable modem or a group of cable modems from DOCSIS load balance based on their device type, MAC address, and Organizational Unique Identifier (OUI) using the cable load-balance exclude command in global configuration mode.
How to Configure Cable Modem Steering on the CMTS Router
This section describes the following required and optional procedures:
Configuring an
Upstream Channel Class ID
This
configuration is optional. A channel class ID must be configured for an
upstream logical channel if you want to configure UCD TLV ranging hold-off on
the CMTS router.
Procedure | Command or Action | Purpose |
---|
Step 1 | enable
Example:
Router> enable
|
Enables
privileged EXEC mode.
- Enter your password if
prompted.
|
Step 2 | configure
terminal
Example:
Router# configure terminal
|
Enters global
configuration mode.
|
Step 3 | controller
upstream-cable slot/subslot/controller-port-number
Example:
Router(config)# controller Upstream-Cable 3/0/0
|
Specifies the
cable interface and enters cable interface configuration mode. Arguments for
this command may vary depending on the CMTS router, line card, and Cisco IOS
software release. For details, see the
Cisco IOS CMTS Cable Command
Reference .
-
Slot— Slot where the interface card resides. The
valid range is from 0 to 3 and 6 to 9 on the Cisco cBR-8 router.
-
Subslot—Subslot where the interface card resides.
The valid value is 0 on the Cisco cBR-8 router.
-
controller-port-number—Controller port number. The
valid values are from 0 to 7 on the Cisco cBR-8 router.
|
Step 4 |
us-channel
us-channel-id
chan-class-id
id
Example:
Router(config-controller)# us-channel 3 chan-class-id ff
|
Configures
the channel class ID for an upstream logical channel.
- us-channel-id—Specifies the upstream channel id.
- id—Channel class ID for the logical upstream
channel in the hexadecimal format. The valid range is from 0 to ffffffff. The
default value is 0.
|
Step 5 | end
Example:
Router(config-controller)# end
|
Returns to
privileged EXEC mode.
|
Configuring an
Upstream Ranging Hold-off Priority Value
This configuration
is optional
Maximum time that
a cable modem can inhibit transmissions on an upstream channel in response to
its ranging class ID matching a bit value in the Ranging Hold-off Priority
field in the cable modem configuration file is 300 seconds (five minutes) per
DOCSIS 3.0 MAC
and Upper Layer Protocols Interface Specification . This default timer
value cannot be changed.
Procedure | Command or Action | Purpose |
---|
Step 1 | enable
Example:
Router> enable
|
Enables
privileged EXEC mode.
- Enter your password if
prompted.
|
Step 2 | configure
terminal
Example:
Router# configure terminal
|
Enters global
configuration mode.
|
Step 3 | controller
upstream-cable slot/subslot/controller-port-number
Example:
Router(config)# controller upstream-cable 3/0/0
|
Specifies the
cable interface and enters cable interface configuration mode. Arguments for
this command may vary depending on the CMTS router, line card, and Cisco IOS
software release. For details, see the
Cisco IOS CMTS Cable Command
Reference .
-
Slot—Slot
where the interface card resides. The valid range is from 0 to 3 and 6 to 9 on
the Cisco cBR-8 router.
-
Subslot—Subslot where the interface card resides.
The valid value is 0 on the Cisco cBR-8 router.
-
controller-port-number—Controller port number. The
valid values are from 0 to 7 on the Cisco cBR-8 router.
|
Step 4 | us-channel
us-channel-id
rng-holdoff
priority
Example:
Router(config-controller)# us-channel 3 rng-holdoff 1
|
Configures
the ranging hold-off priority value for an upstream logical channel.
- us-channel-id—Specifies the upstream channel id.
- rng-holdoff
priority—Specifies the ranging hold-off priority
value in the hexadecimal format. The valid range is from 0 to ffffffff. The
default value is 0.
|
Step 5 | end
Example:
Router(config-controller)# end
|
Returns to
privileged EXEC mode.
|
Verifying and Troubleshooting Cable Modem Steering
This section provides the verification and troubleshooting information:
Verifying an
Upstream Ranging Class ID Configuration
To verify an
upstream ranging class ID of a cable modem, use the
show
cable
modem command with the
verbose
keyword.
Following is a
sample output of the
show
cable
modem verbose command in Cisco IOS-XE Release 3.18.0SP:
Router# show cable modem 68b6.fcfe.22e5 verbose
MAC Address : 68b6.fcfe.22e5
IP Address : 192.168.0.8
IPv6 Address : 2001:DB8:10:1:9951:1972:33F9:9867
Dual IP : Y
Prim Sid : 8
Host Interface : C8/0/0/UB
MD-DS-SG / MD-US-SG : 1 / 2
MD-CM-SG : 0x5A0102
Primary Wideband Channel ID : 3073 (Wi8/0/0:0)
Primary Downstream : Mo8/0/0:0 (RfId : 2304)
Wideband Capable : Y
RCP Index : 3
RCP ID : 00 10 00 00 18
Downstream Channel DCID RF Channel : 45 8/0/0:0
Downstream Channel DCID RF Channel : 46 8/0/0:1
Downstream Channel DCID RF Channel : 47 8/0/0:2
Downstream Channel DCID RF Channel : 48 8/0/0:3
Downstream Channel DCID RF Channel : 49 8/0/0:4
Downstream Channel DCID RF Channel : 50 8/0/0:5
Downstream Channel DCID RF Channel : 51 8/0/0:6
Downstream Channel DCID RF Channel : 52 8/0/0:7
Downstream Channel DCID RF Channel : 53 8/0/0:8
Downstream Channel DCID RF Channel : 54 8/0/0:9
Downstream Channel DCID RF Channel : 55 8/0/0:10
Downstream Channel DCID RF Channel : 56 8/0/0:11
Downstream Channel DCID RF Channel : 57 8/0/0:12
Downstream Channel DCID RF Channel : 58 8/0/0:13
Downstream Channel DCID RF Channel : 59 8/0/0:14
Downstream Channel DCID RF Channel : 60 8/0/0:15
Downstream Channel DCID RF Channel : 61 8/0/0:16
Downstream Channel DCID RF Channel : 62 8/0/0:17
Downstream Channel DCID RF Channel : 63 8/0/0:18
Downstream Channel DCID RF Channel : 64 8/0/0:19
Downstream Channel DCID RF Channel : 65 8/0/0:20
Downstream Channel DCID RF Channel : 66 8/0/0:21
Downstream Channel DCID RF Channel : 67 8/0/0:22
Downstream Channel DCID RF Channel : 68 8/0/0:23
UDC Enabled : N
Extended Upstream Transmit Power : 61dB
Multi-Transmit Channel Mode : Y
Number of US in UBG : 8
Upstream Channel : US0 US1 US2 US3
Ranging Status : sta sta sta sta
Upstream SNR (dB) : 30.62 32.32 18.25 24.26
Upstream Data SNR (dB) : -- -- -- --
Received Power (dBmV) : 0.50 0.00 -0.50 -0.50
Reported Transmit Power (dBmV) : 30.75 30.75 29.25 29.25
Peak Transmit Power (dBmV) : 61.00 61.00 61.00 61.00
Phy Max Power (dBmV) : 48.00 48.00 48.00 48.00
Minimum Transmit Power (dBmV) : 21.00 21.00 21.00 21.00
Timing Offset (97.6 ns): 1800 1800 1800 1800
Initial Timing Offset : 1544 1544 1544 1544
Rng Timing Adj Moving Avg(0.381 ns): -1 0 -1 -1
Rng Timing Adj Lt Moving Avg : -7 0 -7 -7
Rng Timing Adj Minimum : -256 0 -256 -256
Rng Timing Adj Maximum : 65536 65536 65536 65536
Pre-EQ Good : 0 0 0 0
Pre-EQ Scaled : 0 0 0 0
Pre-EQ Impulse : 0 0 0 0
Pre-EQ Direct Loads : 0 0 0 0
Good Codewords rx : 1201 1262 833 656
Corrected Codewords rx : 0 0 169 117
Uncorrectable Codewords rx : 0 0 205 335
Phy Operating Mode : atdma* atdma* atdma* atdma*
Upstream Channel : US4 US5 US6 US7
Ranging Status : sta sta sta sta
Upstream SNR (dB) : 15.53 31.62 31.1 31.87
Upstream Data SNR (dB) : -- -- -- --
Received Power (dBmV) : 0.00 0.00 -0.50 0.50
Reported Transmit Power (dBmV) : 29.25 30.75 30.75 30.75
Peak Transmit Power (dBmV) : 61.00 61.00 61.00 61.00
Phy Max Power (dBmV) : 48.00 48.00 48.00 48.00
Minimum Transmit Power (dBmV) : 21.00 21.00 21.00 21.00
Timing Offset (97.6 ns): 1800 1800 1800 1800
Initial Timing Offset : 1544 1800 1544 1544
Rng Timing Adj Moving Avg(0.381 ns): -1 -1 46 0
Rng Timing Adj Lt Moving Avg : -7 -7 104 0
Rng Timing Adj Minimum : -256 -256 0 0
Rng Timing Adj Maximum : 65536 256 65536 65536
Pre-EQ Good : 0 0 0 0
Pre-EQ Scaled : 0 0 0 0
Pre-EQ Impulse : 0 0 0 0
Pre-EQ Direct Loads : 0 0 0 0
Good Codewords rx : 718 1328 1173 1252
Corrected Codewords rx : 110 0 0 0
Uncorrectable Codewords rx : 298 0 0 0
Phy Operating Mode : atdma* atdma* atdma* atdma*
sysDescr : DOCSIS 3.0 Cable Modem Router
Downstream Power : 7.40 dBmV (SNR = 43.30 dB)
MAC Version : DOC3.0
QoS Provisioned Mode : DOC1.1
Enable DOCSIS2.0 Mode : Y
Modem Status : {Modem= w-online, Security=disabled}
Capabilities : {Frag=N, Concat=N, PHS=Y}
Security Capabilities : {Priv=, EAE=Y, Key_len=}
L2VPN Capabilities : {L2VPN=Y, eSAFE=Y}
Sid/Said Limit : {Max US Sids=8, Max DS Saids=64}
Optional Filtering Support : {802.1P=N, 802.1Q=N, DUT=Y}
Transmit Equalizer Support : {Taps/Symbol= 1, Num of Taps= 24}
Number of CPE : 0(Max CPE = 16)
Number of CPE IPs : 0(Max CPE IPs = 16)
Number of CPE IPv6 : 0(Max CPE IPv6 = 16)
CFG Max-CPE : 16
Flaps : 19(Oct 11 04:00:25)
Errors : 0 CRCs, 0 HCSes
Stn Mtn Failures : 0 aborts, 12 exhausted
Total US Flows : 1(1 active)
Total DS Flows : 1(1 active)
Total US Data : 3294 packets, 577031 bytes
Total US Throughput : 0 bits/sec, 0 packets/sec
Total DS Data : 2263 packets, 200777 bytes
Total DS Throughput : 0 bits/sec, 0 packets/sec
LB group ID assigned (index) : 2153382146 (55810)
LB group ID in config file (index) : N/A (N/A)
LB policy ID : 0
LB policy ID in config file : 0
LB priority : 0
Tag :
Required DS Attribute Mask : 0x0
Forbidden DS Attribute Mask : 0x0
Required US Attribute Mask : 0x0
Forbidden US Attribute Mask : 0x0
Service Type ID :
Service Type ID in config file :
Ranging Class ID : 0x2
Active Classifiers : 0 (Max = NO LIMIT)
CM Upstream Filter Group : 0
CM Downstream Filter Group : 0
CPE Upstream Filter Group : 0
CPE Downstream Filter Group : 0
DSA/DSX messages : permit all
Voice Enabled : NO
DS Change Times : 0
Boolean Services : 2
Number of Multicast DSIDs Support : 63
MDF Capability Mode : 2
IGMP/MLD Version : MLDv2
FCType10 Forwarding Support : Y
Features Bitmask : 0x0
Total Time Online : 9h27m (9h27m since last counter reset)
CM Initialization Reason : BAD_DHCP_ACK
CFG Max IPv6 CPE Prefix : 16 (-1 used)
Additional
References
The following
sections provide references related to the Cable Modem Steering feature.
Standards and
RFCs
Standard
|
Title
|
CM-SP-MULPIv3.0-I07-080215
|
DOCSIS
3.0 MAC and Upper Layer Protocols Interface Specification
|
CM-SP-MULPIv3.0-I18-120329
|
DOCSIS
3.0 MAC and Upper Layer Protocols Interface Specification
|
CM-SP-RFI2.0-I13-080215
|
DOCSIS
2.0 Radio Frequency Interface Specification
|
Technical
Assistance
Description
|
Link
|
The
Cisco Support website provides extensive online resources, including
documentation and tools for troubleshooting and resolving technical issues with
Cisco products and technologies.
To
receive security and technical information about your products, you can
subscribe to various services, such as the Product Alert Tool (accessed from
Field Notices), the Cisco Technical Services Newsletter, and Really Simple
Syndication (RSS) Feeds.
Access
to most tools on the Cisco Support website requires a Cisco.com user ID and
password.
|
http://www.cisco.com/cisco/web/support/index.html
|
Feature
Information for Cable Modem Steering
Use Cisco Feature Navigator to find information about platform support and software image support. Cisco Feature Navigator enables you to determine which software images support a specific software release, feature set, or platform. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
 Note |
The table below lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.
|
Table 2 Feature
Information for Cable Modem Steering on the Cisco CMTS Routers
Feature
Name
|
Releases
|
Feature
Information
|
UCD TLV
for Ranging Hold-off
|
IOS-XE
3.18.0SP
|
The UCD
TLV for Ranging Hold-off feature enables the CMTS router to hold off a cable
modem from initial ranging.
The
following sections provide information about this feature:
The
following commands were introduced or modified:
- us-channel
chan-class-id
- us-channel
rng-holdoff
- show
cable
modem
verbose
|