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Table Of Contents
Route Processor Redundancy Plus (RPR+)
Prerequisites for Route Processor Redundancy Plus (RPR+)
Restrictions for Route Processor Redundancy Plus (RPR+)
Information About Route Processor Redundancy Plus (RPR+)
How to Configure Route Processor Redundancy Plus (RPR+)
Copying an Image onto Active and Standby RSPs
Setting the Configuration Register Boot Variable
Configuration Examples for Route Processor Redundancy Plus (RPR+)
Feature Information for Route Processor Redundancy Plus (RPR+)
Route Processor Redundancy Plus (RPR+)
Route Processor Redundancy (RPR) provides an alternative to the High System Availability (HSA) feature. HSA enables a system to reset and use a standby Route Switch Processor (RSP) if the active RSP fails. Using RPR, you can reduce unplanned downtime because RPR enables a quicker switchover between an active and standby RSP if the active RSP experiences a fatal error.
RPR Plus (RPR+) is an enhancement of the RPR feature. RPR+ keeps the Versatile Interface Processors (VIPs) from being reset and reloaded when a switchover occurs between the active and standby RSPs.
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 for Route Processor Redundancy Plus (RPR+)" section.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Contents
•Prerequisites for Route Processor Redundancy Plus (RPR+)
•Restrictions for Route Processor Redundancy Plus (RPR+)
•Information About Route Processor Redundancy Plus (RPR+)
•How to Configure Route Processor Redundancy Plus (RPR+)
•Configuration Examples for Route Processor Redundancy Plus (RPR+)
•Feature Information for Route Processor Redundancy Plus (RPR+)
Prerequisites for Route Processor Redundancy Plus (RPR+)
RPR and RPR+ require a Cisco 7500 series router loaded with two RSP16s, one RSP16 and one RSP8, two RSP8s, or a combination of RSP2s and RSP4s. If you are using the one RSP16 and one RSP8 combination, you must use the same memory—256 MB—in both RSPs because the secondary RSP must be able to support the primary RSP during a failover.
Restrictions for Route Processor Redundancy Plus (RPR+)
•RSP1s do not support RPR or HSA.
•RPR is supported only on routers that support dual RSPs. Only the Cisco 7507 and Cisco 7513 support dual RSPs.
•RPR+ operates only in a system with VIPs as the line cards. Systems with legacy interface processors default to RPR.
•In RPR+ mode, configuration changes done through Simple Network Management Protocol (SNMP) may not be automatically configured on the standby RSP after a switchover occurs.
•RPR+ does not work on routers configured with MPLS.
Information About Route Processor Redundancy Plus (RPR+)
•RPR
•RPR+
RPR
Route Processor Redundancy (RPR) provides an alternative to the High System Availability (HSA) feature currently available on Cisco 7500 series routers. HSA enables a system to reset and use a standby Route Switch Processor (RSP) if the active RSP fails.
Using RPR, you can reduce unplanned downtime. RPR enables a quicker switchover between an active and standby RSP if the active RSP experiences a fatal error. When you configure RPR, the standby RSP loads a Cisco IOS image on bootup and initializes itself in standby mode. In the event of a fatal error on the active RSP, the system switches to the standby RSP, which reinitializes itself as the active RSP, reloads all of the line cards, and restarts the system.
RPR+
The RPR+ feature is an enhancement of the RPR feature on Cisco 7500 series routers. RPR+ keeps the VIPs from being reset and reloaded when a switchover occurs between the active and standby RSPs. Because VIPs are not reset and microcode is not reloaded on the VIPs, and the time needed to parse the configuration is eliminated, switchover time is reduced to 30 seconds.
Table 1 describes the average time for a router to switchover to a standby RSP if the active RSP fails.
Table 1 Average Switchover Time Comparison Table
Feature Time to Immediately Switch a Packet on New RSP After Failover Expected Overall Time to Have New RSP in New High Availability State After Failover NotesHSA
10 minutes
20 minutes
System default.
RPR
5 minutes
15 minutes
VIPs and legacy interface processors (IPs) supported.
RPR+
30 seconds
11 minutes
VIPs supported.1
1 Legacy IPs default to RPR. To allow RPR+ for VIPs when up to two legacy IPs exist in the router, you must configure the service single-slot-reload-enable command. If you do not enable the service single-slot-reload-enable command or if you have more than two legacy IPs, all the line cards are reloaded.
Note Table 1 shows average switchover times. Recovery time will vary depending on the configuration of the router.
In Table 1 we have noted that RPR+ supports up to two legacy IPs in the router if the service single-slot-reload-enable command is configured. By default, the existence of any legacy IPs in the router causes all the line cards to be reloaded during an RPR+ switchover and a message similar to the following to be displayed:
%HA-2-MAX_NO_Quiesce: 1 linecard(s) not quiesced exceeds limit of 0, all slots will be reloaded.If the service single-slot-reload-enable command is configured, then the NO_Quiesce limit is set to two, allowing two quiesce failures during an RPR+ switchover. When more than two legacy IPs exist in the router, all the line cards are reloaded during an RPR+ switchover, and a message similar to the following is displayed:
%HA-2-MAX_NO_Quiesce: 3 linecard(s) not quiesced exceeds limit of 2, all slots will be reloaded.How to Configure Route Processor Redundancy Plus (RPR+)
•Copying an Image onto Active and Standby RSPs (required)
•Setting the Configuration Register Boot Variable (optional)
•Configuring RPR+ (required)
•Verifying RPR+ (optional)
Copying an Image onto Active and Standby RSPs
Perform this task to use TFTP to copy a high availability Cisco IOS image onto the active and standby RSPs.
Prerequisites
Before copying a file to flash memory, you must ensure that there is enough space available in flash memory. Compare the size of the file that you are copying to the amount of available flash memory shown. If the space available is less than the space required by the file that you will copy, the copy process will not continue and and error message similar to the following will be displayed:
%Error copying tftp://image@server/tftpboot/file-location/image-name (Not enough space on
device).SUMMARY STEPS
1. enable
2. copy tftp slotslot-number:
3. copy tftp slaveslotslot-number:
DETAILED STEPS
Step 1 enable
Enables privileged EXEC mode. Enter your password if prompted.
Router> enableStep 2 copy tftp slotslot-number:
Use this command to copy a high availability Cisco IOS image onto the flash memory card of the active RSP. The slotslot-number keyword and argument specify the flash memory card of the active RSP.
Router# copy tftp slot0:Address or name of remote host []? ip-addressEnter the IP address of the TFTP server that contains the new image.
Router# 172.18.2.3Source filename []? image-name
Enter the name of the image file that you are copying to the flash memory card.
Router# rsp-pv-mzDestination file name? [image-name1] <Return>Enter the name under which you want the image file to appear at the destination. The destination name is optional. To use the same image name as the source file, press the Enter key.
Accessing tftp://ip-address/...
Step 3 copy tftp slaveslotslot-number:
Use this command to copy a high availability Cisco IOS image onto the flash memory card of the standby RSP. The slaveslotslot-number keyword and argument specify the flash memory card of the standby RSP.
Router# copy tftp slaveslot0:Address or name of remote host []? ip-addressEnter the IP address of the TFTP server that contains the new image.
Router# 172.18.2.3Source filename []? image-name
Enter the name of the image file that you are copying to the flash memory card.
Router# rsp-pv-mzDestination file name? [image-name1] <Return>Enter the name under which you want the image file to appear at the destination. The destination name is optional. To use the same image name as the source file, press the Enter key.
Accessing tftp://ip-address/...
What to Do Next
If you do not want to modify the software configuration register boot field, proceed to the "Configuring RPR+" section.
Setting the Configuration Register Boot Variable
Perform this optional task to modify the software configuration register boot field to ensure that the system boots the same image as that specified by the hw-module slot image command in the "Configuring RPR+" section.
SUMMARY STEPS
1. enable
2. show version
3. configure terminal
4. boot system flash slotslot-number:[image-name]
5. config-register value
6. exit
7. reload
DETAILED STEPS
Command or Action PurposeStep 1
enable
Example:Router> enable
Enables privileged EXEC mode.
•Enter your password if prompted.
Step 2
show version
Example:Router# show version
Displays the current configuration register setting at the end of the display.
Step 3
configure terminal
Example:Router# configure terminal
Enters global configuration mode.
Step 4
boot system flash slotslot-number:[image-name]
Example:Router(config)# boot system flash slot0:rsp-pv-mz
Specifies the filename of an image stored in flash memory.
•slot-number:—Specifies the active RSP slot where the flash memory card is located. Valid slot numbers are 0 and 1 for the Cisco 7500 series RSP.
•image-name—Specifies the name of the image. It is recommended that you set the boot variable so that the system boots the same image as that specified by the hw-module slot slot-number image file-spec command. See Step 3 of the "Configuring RPR+" section.
Step 5
config-register value
Example:Router(config)# config-register 0x2102
Modifies the existing configuration register setting to reflect the way in which you want to load a system image.
•Use the value argument to specify the configuration register setting. Valid values are in the range from 0x0 to 0xFFFF.
•In this example, when a reload command is issued, the router automatically boots the image specified in the boot system flash image-name configuration.
Step 6
exit
Example:Router(config)# exit
Exits global configuration mode and returns to privileged EXEC mode.
Step 7
reload
Example:Router# reload
Reboots the router to make your configuration changes take effect.
Examples
The following is sample partial output from the show version command; the output displays the current configuration register setting.
Router# show versionCisco IOS Software, C7500 Software (C7500-IPBASE-MZ), Version 12.3(7)T, RELEASE)TAC Support: http://www.cisco.com/tacCopyright (c) 1986-2004 by Cisco Systems, Inc.Compiled Fri 16-Jan-04 18:03 by engineerROM: System Bootstrap, Version 12.1(3r)T2, RELEASE SOFTWARE (fc1)...Configuration register is 0x2102Configuring RPR+
Perform this task to configure RPR+.
Restrictions
RPR+ operates only in a system with VIPs as the line cards. Systems with legacy IPs default to RPR mode. Up to two legacy IPs can be supported by RPR+ if the service single-slot-reload-enable command is configured. For more details, see the "RPR+" section.
SUMMARY STEPS
1. enable
2. configure terminal
3. hw-module slot slot-number image file-spec
4. Repeat Step 3 for the standby RSP.
5. redundancy
6. mode {hsa | rpr | rpr-plus}
7. exit
8. copy system:running-config nvram:startup-config
9. hw-module sec-cpu reset
DETAILED STEPS
Verifying RPR+
Perform this task to verify whether RPR+ is configured on the router and to display other redundancy statistics.
SUMMARY STEPS
1. enable
2. show redundancy
DETAILED STEPS
Step 1 enable
Enables privileged EXEC mode. Enter your password if prompted.
Router> enableStep 2 show redundancy
Use this command to verify what type of redundancy is configured on the router and to display other redundancy information.
Router# show redundancyOperating mode is rpr-plusredundancy mode rpr-plushw-module slot 2 image disk0:rsp-pv-mzhw-module slot 3 image disk0:rsp-pv-mzThe system total uptime since last reboot is 5 days, 19 hours 36 minutes.The system has experienced 27 switchovers.The system has been active (become master) for 5 days, 15 hours 14 minutes.Reason for last switchover:User forced.
Configuration Examples for Route Processor Redundancy Plus (RPR+)
Configuring RPR+: Example
In the following example, the active RSP is installed in slot 2 and the standby RSP is installed in slot 3 of a Cisco 7507 router.
Router# copy tftp slot0:rsp-pv-mzRouter# copy tftp slaveslot0:rsp-pv-mzRouter# configure terminalRouter(config)# hw-module slot 2 image slot0:rsp-pv-mzRouter(config)# hw-module slot 3 image slot0:rsp-pv-mzRouter(config)# redundancyRouter(config-r)# mode rpr-plusRouter(config-r)# endRouter# hw-module sec-cpu resetRouter# show running-configversion 12.3(7)Tservice timestamps debug uptimeservice timestamps log uptimeno service password-encryptionservice single-slot-reload-enable!hostname Router!boot system rcp://path/to/image/rsp-boot-mzboot system tftp://path/to/image/rsp-boot-mzboot bootldr bootflash:rsp-boot-mzenable password password!redundancymode rpr-plus ! Indicates that redundancy mode has been configured for RPR+.!hw-module slot 2 image slot0:rsp-pv-mzhw-module slot 3 image slot0:rsp-pv-mzip subnet-zeroip rcmd remote-username Routerip cef distributedip host iphost 192.168.0.1mpls traffic-eng auto-bw timers!!controller T3 6/0/0clock source line!!interface Ethernet0/0/0ip address 10.0.0.1 255.255.0.0no ip directed-broadcastip route-cache distributedno keepalive...exec-timeout 0 0history size 40transport preferred nonetransport input noneline aux 0line vty 0 4login!endAdditional References
Related Documents
Standards
Standards TitleNo new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.
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MIBs
RFCs
RFCs TitleNo new or modified RFCs are supported by this feature, and support for existing RFCs has not been modified by this feature.
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Technical Assistance
Feature Information for Route Processor Redundancy Plus (RPR+)
Table 2 lists the release history for this feature.
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 Table 2 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.
Glossary
Active RSP—The RSP that controls and runs the routing protocols and that presents the system management interface.
HSA—High System Availability. HSA enables a system to reset and use a standby RSP if the active RSP fails.
RPR—Route Processor Redundancy. An alternative to HSA that reduces unplanned downtime.
RPR+—Route Processor Redundancy Plus. An enhancement to RPR in which the standby RSP is fully initialized. An RPR+ switchover does not involve resetting line cards or reloading line card software for VIPs. Legacy interface processors are reset and reloaded during switchover.
RSP—Route Switch Processor. The Route Processor on the Cisco 7500 series router.
Standby RSP—The RSP that waits ready to take over the functions of the active RSP in the event of unplanned or planned downtime.
Note Refer to Internetworking Terms and Acronyms for terms not included in this glossary.
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Any Internet Protocol (IP) addresses used in this document are not intended to be actual addresses. Any examples, command display output, and figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses in illustrative content is unintentional and coincidental.
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