Table Of Contents
High System Availability (HSA)
Understand Master and Slave Operation
Understand Implementation Methods
Understand System Requirements
Configure HSA Operation Task List
Ensure That Both RSP Cards Contain the Same Configuration File
Ensure That Both RSP Cards Contain the Same System Image
Ensure That Both RSP Cards Contain the Same Microcode Image
Specify Different Startup Images for the Master and Slave RSP
Set Environment Variables on the Master and Slave RSP
Automatically Set Environment Variables on the Slave RSP
Manually Set Environment Variables on the Slave RSP
Monitor and Maintain HSA Operation
Override the Slave Image Bundled with the Master Image
Manually Synchronize Configuration Files
Troubleshoot a Failed RSP Card
Disable Access to Slave Console
Display Information about Master and Slave RSP Cards
High System Availability (HSA)
High system availability (HSA) is a feature on Cisco 7507 and Cisco 7513 routers which allows you to install two RSP cards in a single router to improve system availability.
Two RSP cards in a router provide the most basic level of increased system availability through a "cold restart" feature. A "cold restart" means that when one RSP card fails, the other RSP card reboots the router. In this way, your router is never in a failed state for very long, thereby increasing system availability.
When one RSP card takes over operation from another, system operation is interrupted. This change is similar to issuing the reload command. The following events occur when one RSP card fails and the other takes over:
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The router stops passing traffic.
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Note
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The boot ROM is on a SIMM in the RSP2 and cannot be upgraded. You can identify the boot ROM version on your RSP2 by issuing the show version | begin ROM command in privileged EXEC mode.Understand Master and Slave Operation
A router configured for HSA operation has one RSP card that is the master and one that is the slave. The master RSP card functions as if it were a single processor, controlling all functions of the router. The slave RSP card does nothing but actively monitor the master for failure.
A system crash can cause the master RSP to fail or go into a nonfunctional state. When the slave RSP detects a nonfunctional master, the slave resets itself and takes part in master-slave arbitration. Master-slave arbitration is a ROM monitor process that determines which RSP card is the master and which is the slave upon startup (or reboot).
If a system crash causes the master RSP to fail, the slave RSP becomes the new master RSP and uses its own system image and configuration file to reboot the router. The failed RSP card now becomes the slave. The failure state of the slave (formerly the master) can be accessed from the console via the show stacks command.
With HSA operation, the following items are important to note:
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Understand Implementation Methods
There are two common ways to use HSA. You can use HSA for:
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Use this method to protect against an RSP card failure. With this method, you configure both RSP cards with the same software image and configuration information. Also, you configure the router to automatically synchronize configuration information on both cards when changes occur.
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Use this method to protect against critical Cisco IOS software errors in a particular release. With this method, you configure the RSP cards with different software images, but with the same configuration information. If you are using new or experimental Cisco IOS software, consider using the software error protection method.
You can also use HSA for advanced implementations. For example, you can configure the RSP cards with the following:
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Understand System Requirements
To configure HSA operation, you must have a Cisco 7507 or Cisco 7513 containing two RSP processor cards and Cisco IOS Release 11.1 or later.
Configure HSA Operation Task List
When configuring HSA operation, complete the tasks in the following sections. The first two and last two tasks are required for both implementations. The third and fourth tasks relates to simple hardware backup. The fifth task relates to software error protection only.
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Specify the Default Slave RSP
Because your view of the environment is always from the master RSP perspective, you define a default slave RSP. The router uses the default slave information when booting as follows:
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To define the default slave RSP, use the following command, beginning in privileged EXEC mode:
Upon the next system reboot, the above changes take effect (if both RSP cards are operational). Thus, the specified default slave becomes the slave RSP card. The other RSP card takes over mastership of the system and controls all functions of the router.
If you do not specifically define the default slave RSP, the RSP card located in the higher number processor slot is the default slave. On the Cisco 7507, processor slot 3 contains the default slave RSP. On the Cisco 7513, processor slot 7 contains the default slave RSP.
The following example sets the default slave RSP to processor slot 2 on a Cisco 7507:
Router# configure terminalRouter (config)# slave default-slot 2Router (config)# endRouter# copy system:running-config nvram:startup-configEnsure That Both RSP Cards Contain the Same Configuration File
With both the simple hardware backup and software error protection implementation methods, you always want your master and slave configuration files to match. To ensure that they match, turn on automatic synchronization. In automatic synchronization mode, the master copies its startup configuration to the slave's startup configuration when you issue a copy command that specifies the master's startup configuration (nvram:startup-config) as the target.
Automatic synchronization mode is on by default; however, to turn it on manually, use the following commands, beginning in privileged EXEC mode:
The following example turns on automatic configuration file synchronization:
Router# configure terminalRouter (config)# slave auto-sync configRouter (config)# endRouter# copy system:running-config nvram:startup-configEnsure That Both RSP Cards Contain the Same System Image
For simple hardware backup, ensure that both RSP cards have the same system image.
To ensure that both RSP cards have the same system image, use the following commands in EXEC mode:
The following example ensures that both RSP cards have the same system image. Note that because no environment variables are set, the default environment variables are in effect for both the master and slave RSP. Therefore, the router will boot the image in slot 0.
Router# show bootvarBOOT variable =CONFIG_FILE variable =Current CONFIG_FILE variable =BOOTLDR variable does not existConfiguration register is 0x0current slave is in slot 7BOOT variable =CONFIG_FILE variable =BOOTLDR variable does not existConfiguration register is 0x0Router# dir slot0:-#- -length- -----date/time------ name1 3482498 May 4 1993 21:38:04 rsp-k-mz11.27993896 bytes available (1496 bytes used)Router# dir slaveslot0:-#- -length- -----date/time------ name1 3482498 May 4 1993 21:38:04 rsp-k-mz11.17993896 bytes available (1496 bytes used)Router# delete slaveslot0:rsp-k-mz11.1Router# copy slot0:rsp-k-mz11.2 slaveslot0:rsp-k-mz11.2Ensure That Both RSP Cards Contain the Same Microcode Image
To ensure that interface processors will load the same microcode, regardless of which RSP is used, use the following commands beginning in privileged EXEC mode:
The following example ensures that both RSP cards have the same microcode image. Notice that slots 0, 1, 4, 9, and 10 load microcode from the bundled software, as noted by the statement "software loaded from system." Slot 11, the (Fast Serial Interface Processor) FSIP processor, doesnot use the microcode bundled with the system. Instead, it loads the microcode from slot0:pond/bath/rsp_fsip20-1. Thus, you must ensure that the slave RSP has a copy of the same FSIP microcode in the same location.
Router# show controller cbusMEMD at 40000000, 2097152 bytes (unused 416, recarves 3, lost 0)RawQ 48000100, ReturnQ 48000108, EventQ 48000110BufhdrQ 48000128 (2948 items), LovltrQ 48000140 (5 items, 1632 bytes)IpcbufQ 48000148 (16 items, 4096 bytes)3571 buffer headers (48002000 - 4800FF20)pool0: 28 buffers, 256 bytes, queue 48000130pool1: 237 buffers, 1536 bytes, queue 48000138pool2: 333 buffers, 4544 bytes, queue 48000150pool3: 4 buffers, 4576 bytes, queue 48000158slot0: EIP, hw 1.5, sw 20.00, ccb 5800FF30, cmdq 48000080, vps 4096software loaded from systemEthernet0/0, addr 0000.0ca3.cc00 (bia 0000.0ca3.cc00)gfreeq 48000138, lfreeq 48000160 (1536 bytes), throttled 0rxlo 4, rxhi 42, rxcurr 0, maxrxcurr 2txq 48000168, txacc 48000082 (value 27), txlimit 27.........slot1: FIP, hw 2.9, sw 20.02, ccb 5800FF40, cmdq 48000088, vps 4096software loaded from systemFddi1/0, addr 0000.0ca3.cc20 (bia 0000.0ca3.cc20)gfreeq 48000150, lfreeq 480001C0 (4544 bytes), throttled 0rxlo 4, rxhi 165, rxcurr 0, maxrxcurr 0txq 480001C8, txacc 480000B2 (value 0), txlimit 95slot4: AIP, hw 1.3, sw 20.02, ccb 5800FF70, cmdq 480000A0, vps 8192software loaded from systemATM4/0, applique is SONET (155Mbps)gfreeq 48000150, lfreeq 480001D0 (4544 bytes), throttled 0rxlo 4, rxhi 165, rxcurr 0, maxrxcurr 0txq 480001D8, txacc 480000BA (value 0), txlimit 95slot9: MIP, hw 1.0, sw 20.02, ccb 5800FFC0, cmdq 480000C8, vps 8192software loaded from systemT1 9/0, applique is Channelized T1gfreeq 48000138, lfreeq 480001E0 (1536 bytes), throttled 0rxlo 4, rxhi 42, rxcurr 0, maxrxcurr 0txq 480001E8, txacc 480000C2 (value 27), txlimit 27.......slot10: TRIP, hw 1.1, sw 20.00, ccb 5800FFD0, cmdq 480000D0, vps 4096software loaded from systemTokenRing10/0, addr 0000.0ca3.cd40 (bia 0000.0ca3.cd40)gfreeq 48000150, lfreeq 48000200 (4544 bytes), throttled 0rxlo 4, rxhi 165, rxcurr 1, maxrxcurr 1txq 48000208, txacc 480000D2 (value 95), txlimit 95.........slot11: FSIP, hw 1.1, sw 20.01, ccb 5800FFE0, cmdq 480000D8, vps 8192software loaded from flash slot0:pond/bath/rsp_fsip20-1Serial11/0, applique is Universal (cable unattached)gfreeq 48000138, lfreeq 48000240 (1536 bytes), throttled 0rxlo 4, rxhi 42, rxcurr 0, maxrxcurr 0txq 48000248, txacc 480000F2 (value 5), txlimit 27...........Router# dir slot0:pond/bath/rsp_fsip20-1-#- -length- -----date/time------ name3 10242 Jan 01 1995 03:46:31 pond/bath/rsp_fsip20-1Router# dir slaveslot0:pond/bath/rsp_fsip20-1No such file4079832 bytes available (3915560 bytes used)Router# copy slot0:pond/bath/rsp_fsip20-1 slaveslot0:4079704 bytes available on device slaveslot0, proceed? [confirm]Router# dir slaveslot0:pond/bath/rsp_fsip20-1-#- -length- -----date/time------ name3 10242 Mar 01 1993 02:35:04 pond/bath/rsp_fsip20-14069460 bytes available (3925932 bytes used)Specify Different Startup Images for the Master and Slave RSP
For software error protection, the RSP cards should have different system images.
When the factory sends you a new Cisco 7507 or Cisco 7513 with two RSPs, you receive the same system image on both RSP cards. For the software error protection method, you need two different software images on the RSP cards. Thus, you copy a desired image to the master RSP card and modify the boot system commands to reflect booting two different system images. Each RSP card uses its own image to boot the router when it becomes the master.
To specify different startup images for the master and slave RSP, use the following commands beginning in EXEC mode:
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dir {bootflash: | slot0: | slot1:}
Verify the location and version of the master RSP software image.
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dir {slavebootflash: | slaveslot0: | slaveslot1:}
Determine if the slave RSP contains the same software image in the same location.
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copy source-url {bootflash: | slot0: | slot1:}
Copy a different system image to the master RSP.
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configure terminal
Enter configuration mode from the terminal.
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boot system flash bootflash:[filename]
boot system flash slot0:[filename]
boot system flash slot1:[filename]
From global configuration mode, configure the master RSP to boot the new image from the appropriate location.
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boot system flash bootflash:[filename]
boot system flash slot0:[filename]
boot system flash slot1:[filename]
Also, add a boot system command that specifies the slave's boot image and location. This is the boot image that the slave uses when it becomes the master RSP and boots the system. Note that the because the slave will boot this image when the slave is actually the new master RSP, the command syntax does not use a "slave" prefix.
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boot system {rcp | tftp | ftp} [filename] [ip-address]
(Optional) Configure the master RSP to boot from a network server.
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config-register value1
Set the configuration register to enable the system to load the system image from a network server or from Flash.
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end
Exit configuration mode.
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copy system:running-config nvram:startup-config
Save the configuration file to the master's startup configuration. Because automatic synchronization is turned on, this step saves the boot system commands to the master and slave startup configuration.
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reload
Reset the router with the new configuration information.
1 Refer to the "Modify the Configuration Register Boot Field" section for more information on systems that can use this command to modify the software configuration register.
HSA: Upgrading to a New Software Version Example
In this example, assume the following:
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illustrates the software error protection configuration for this example. The configuration commands for this configuration follow the figure.
Figure 12 Software Error Protection: Upgrading to a New Software Version
Because you always view the environment from the master RSP perspective, in the following command you view the master's slot 0 to verify the location and version of the master's software image:
Router# dir slot0:-#- -length- -----date/time------ name1 3482496 May 4 1993 21:38:04 rsp-k-mz11.17993896 bytes available (1496 bytes used)Now view the slave's software image location and version:
Router# dir slaveslot0:-#- -length- -----date/time------ name1 3482496 May 4 1993 21:38:04 rsp-k-mz11.17993896 bytes available (1496 bytes used)Because you want to run the Release 12.0 system image on one RSP card and the Release 11.1 system image on the other RSP card, copy the Release 12.0 system image to the master's slot 0:
Router# copy tftp: slot0:rsp-k-mz12.0Enter global configuration mode and configure the system to boot first from a Release 12.0 system image and then from a Release 11.1 system image.
Router# configure terminalRouter (config)# boot system flash slot0:rsp-k-mz12.0Router (config)# boot system flash slot0:rsp-k-mz11.1With this configuration, when the slot 6 RSP card is master, it looks first in its PCMCIA slot 0 for the system image file rsp-k-mz11.2 to boot. Finding this file, the router boots from that system image. When the slot 7 RSP card is master, it also looks first in its slot 0 for the system image file rsp-k-mz12.0 to boot. Because that image does not exist in that location, the slot 7 RSP card looks for the system image file rsp-k-mz11.1 in slot 0 to boot. Finding this file in its PCMCIA slot 0, the router boots from that system image. In this way, each RSP card can reboot the system using its own system image when it becomes the master RSP card.
Configure the system further with a fault-tolerant booting strategy:
Router (config)# boot system tftp rsp-k-mz11.1 192.168.1.25Set the configuration register to enable loading of the system image from a network server or from Flash and save the changes to the master and slave startup configuration file:
Router (config)# config-register 0x010FRouter (config)# endRouter# copy system:running-config nvram:startup-configReload the system so that the master RSP uses the new Release 12.0 system image:
Router# reloadHSA: Backing Up with an Older Software Version Example
In the following example, assume the following:
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In this scenario, you begin with the configuration shown in .
Figure 13 Software Error Protection: Backing Up with an Older Software Version, Part I
First, copy the rsp-k-mz11.1 image to the master and slave RSP card, as shown in .
Figure 14 Software Error Protection: Backing Up with an Older Software Version, Part II
Next, you delete the rsp-k-mz11.2 image from the slave RSP card. The final configuration is shown in .
Figure 15 Software Error Protection: Backing Up with an Older Software Version, Part III
The following commands configure software error protection for this example scenario.
View the master and slave slot 0 to verify the location and version of their software images:
Router# dir slot0:-#- -length- -----date/time------ name1 3482498 May 4 1993 21:38:04 rsp-k-mz11.27993896 bytes available (1496 bytes used)Router# dir slaveslot0:-#- -length- -----date/time------ name1 3482498 May 4 1993 21:38:04 rsp-k-mz11.27993896 bytes available (1496 bytes used)Copy the Release 11.1 system image to the master and slave slot 0:
Router# copy tftp: slot0:rsp-k-mz11.1Router# copy tftp: slaveslot0:rsp-k-mz11.1Delete the rsp-k-mz11.2 image from the slave RSP card:
Router# delete slaveslot0:rsp-k-mz11.2Configure the system to boot first from a Release 11.2 system image and then from a Release 11.1 system image:
Router# configure terminalRouter (config)# boot system flash slot0:rsp-k-mz11.2Router (config)# boot system flash slot0:rsp-k-mz11.1Configure the system further with a fault-tolerant booting strategy:
Router (config)# boot system tftp rsp-k-mz11.1 192.168.1.25Set the configuration register to enable loading of the system image from a network server or from Flash and save the changes to the master and slave startup configuration file:
Router (config)# config-register 0x010FRouter (config)# endRouter# copy system:running-config nvram:startup-config
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Set Environment Variables on the Master and Slave RSP
You can optionally set environment variables on both RSP cards in a Cisco 7507 and Cisco 7513. For more information on environment variables, refer to the "Set Environment Variables" section.
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You set environment variables on the master RSP just as you would if it were the only RSP card in the system. Refer to the following sections for more information on these steps:
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You can set the same environment variables on the slave RSP card, manually or automatically. The following sections describe these two methods:
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Automatically Set Environment Variables on the Slave RSP
With automatic synchronization turned on, the system automatically saves the same environment variables to the slave's startup configuration when you set the master's environment variables and save them.
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To set environment variables on the slave RSP when automatic synchronization is on, use the following commands beginning in global configuration mode:
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Set the master's environment variables as described in the "Controlling Environment Variables," "Set the BOOTLDR Environment Variable," and "Specify the CONFIG_FILE Environment Variable (Class A Flash File Systems)" sections.
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copy system:running-config nvram:startup-config
Save the settings to the startup configuration. This also puts the information under that RSP card's ROM monitor control.
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show bootvar
Verify the environment variable settings.
Manually Set Environment Variables on the Slave RSP
If you disable automatic synchronization of configuration files, you must manually synchronize the slave's configuration file to the master's configuration file to store environment variables on the slave RSP.
Once you set the master's environment variables, you can manually set the same environment variables on the slave RSP card using the slave sync config command.
To manually set environment variables on the slave RSP, use the following commands beginning in global configuration mode:
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Set the master's environment variables as described in the "Controlling Environment Variables," "Set the BOOTLDR Environment Variable," and "Specify the CONFIG_FILE Environment Variable (Class A Flash File Systems)" sections.
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end
Exit global configuration mode.
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copy system:running-config nvram:startup-config
Save the settings to the startup configuration. This also puts the information under that RSP card's ROM monitor control.
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slave sync config
Save the same environment variables to the slave RSP by manually synchronizing their configuration files.
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show bootvar
Verify the environment variable settings.
Monitor and Maintain HSA Operation
To monitor and maintain HSA operation, complete the following tasks in the following sections:
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Override the Slave Image Bundled with the Master Image
You can override the slave image that is bundled with the master image. To do so, use the following command in global configuration mode:
Manually Synchronize Configuration Files
You can manually synchronize configuration files and ROM monitor environment variables on the master and slave RSP card. To do so, use the following command in privileged EXEC mode:
CautionWhen you install a second RSP card for the first time, you must immediately configure it using the slave sync config command. This ensures that the new slave is configured consistently with the master. Failure to do so can result in an unconfigured slave RSP card taking over mastership of the router when the master fails, rendering the network inoperable.
The slave sync config command is also a useful tool for more advanced implementation methods not discussed in this chapter.
Troubleshoot a Failed RSP Card
When a new master RSP card takes over mastership of the router, it automatically reboots the failed RSP card as the slave RSP card. You can access the state of the failed RSP card in the form of a stack trace from the master console using the show stacks command.
You can also manually reload a failed, inactive RSP card from the master console. This task returns the card to the active slave state. If the master RSP fails, the slave will be able to become the master. To manually reload the inactive RSP card, use the following command in global configuration mode:
Disable Access to Slave Console
The slave console does not have enable password protection. Thus, an individual connected to the slave console port can enter privileged EXEC mode and view or erase the configuration of the router. Use the no slave terminal command to disable slave console access and prevent security problems. When the slave console is disabled, users cannot enter commands.
If slave console access is disabled, the following message appears periodically on the slave console:
%%Slave terminal access is disabled. Use "slave terminal" command in master RSP configuration mode to enable it.Display Information about Master and Slave RSP Cards
You can also display information about both the master and slave RSP cards. To do so, use any of the following commands in EXEC mode:
