When configuring HA, go to these sections
for information you are interested in:
l
Introduction
to HA
l
Configuring
HA
l
Displaying
and Maintaining HA
l
HA
Configuration Example
1.1 Introduction
to HA
High Availability (HA for short) feature can
be used to achieve a higher degree of system availability. Devices supporting
HA are normally equipped with two Switching and Routing Process Units (SRPU for
short), with one being the active main board (AMB) that works under master mode
and the other being the standby main board (SMB) that works under slave mode. With
the synchronization function the SMB can work under the same system
configuration. Thus, in the event of an AMB failure, the SMB will immediately
switch over to function as an AMB (referred to as switchover hereafter),
ensuring that the device works properly and its configuration is synchronized
with that of the AMB.
Switchover occurs in the following cases:
l
AMB failure
l
The AMB is plugged out
l
SNMP
l
Manual switchover
A switchover takes place in the following order
in the event of an AMB failure:
1)
The SMB automatically connects and controls system
bus while the original AMB disconnects from it.
2)
The original SMB becomes the new AMB whereas the
original AMB automatically reboots and functions as the new SMB.
We discuss switchover through user command
line in this chapter.
1.2 Configuring HA
|
To do…
|
Use the command…
|
Remarks
|
|
Enter system view
|
system-view
|
—
|
|
Ignore version check of the AMB and SMB
|
ha slave-ignore-version-check
|
Optional
Version check is enabled by default.
|
|
Enable the manual switchover between the AMB
and SMB
|
slave switchover
[ enable ]
|
Optional
Enabled by default
|
|
Manually configure switchover between the
AMB and SMB
|
slave switchover
|
Optional
|
|
Manually configure the SMB restart
|
slave restart
|
Optional
|
|
Enable Full Mesh forwarding enhance mode
|
fullmesh-enhance { enable | disable }
|
Required
Disabled by default.
|
Caution:
l
The SMB does not support any system
configuration commands. Therefore, users cannot execute any commands in the SMB
unless it has replaced the original AMB and has become the new AMB.
l
After the SMB has restarted, the AMB will perform
initial synchronization on the SMB. During this process if the user presses
<Enter>, the system will prompt the user no command can be input. After
the initial synchronization is completed, the user can execute all the
configuration commands in the AMB and the AMB and SMB will keep a real-time synchronization
process, meaning the configuration of the user on the AMB will be copied to the
SMB to ensure the consistency of the current configuration of the AMB and SMB.
l
A switchover capable device cannot be updated
with a software specific with centralized device as this will result in an
unavailable system.
l
If only one SRPU is in the slot, the Full Mesh
enhance mode does not take effect.
l
The S9505 switch does not support the
fullmesh-enhance command.
l
When the system works in load balancing mode, it
activates the Full Mesh enhance mode if this mode is configured.
l
When the system works in active and standby mode,
it does not activate the Full Mesh enhance mode if this mode is configured. In
this case, you need to switch the system to the load balancing mode to activate
the Full Mesh enhance mode.
1.3 Displaying and Maintaining HA
|
To do…
|
Use the command…
|
Remarks
|
|
Display the
switchover state
|
display
switchover state [ slot-id ]
|
Available
in any view
|
|
Display
Full Mesh forwarding information
|
display
fullmesh-enhance
|
Available
in any view
|
1.4 HA Configuration Examples
I. Configuration prerequisites
Dynamic upgrade of image files of the AMB
and SMB.
II. Configuration procedure
1)
Download the update software
Through remote online update commands, download
new application program to the AMB. Use the FTP, TFTP, or XModem to download
the application program to the AMB and save it in the flash.
2)
Copy the software to the SMB
Assume the update application is test.app,
slot 0 is the AMB, and slot 1 is the SMB.
<Sysname> copy test.app
slot1#flash:/test.app
3)
Designate the newly downloaded update
application to be the executive software of the AMB and SMB.
<Sysname> boot-loader file
flash:/test.app slot 0 main
<Sysname> boot-loader file slot1#flash:/test.app
slot 1 main
4)
Restart the SMB.
<Sysname> system-view
[Sysname] slave restart
The slave will reset!
Continue?[Y/N]:y
5)
Copy the configuration file to the SMB.
If the SMB is working properly, system will
prompt that it is in an active state. As long as the auto-update function is
enabled, the configuration file will be copied to the SMB while the AMB is
saving the same file.
[Sysname] slave auto-update config
[Sysname] quit
<Sysname> save
6)
Manually configure the switch over between the AMB
and SMB.
<Sysname> system-view
[Sysname] slave switchover
Caution!!! Confirm switch slave to
master[Y/N]?y
After the switchover, the original AMB will
reset, restart, and update its application file. Thus, the whole system has its
application upgraded dynamically.
I. Configuration prerequisites
l
Two SRPUs work in active and standby mode.
l
Set the Full Mesh forwarding to enhance mode to
optimize the Full Mesh forwarding performance in the system.
II. Configuration procedure
# Enter system view.
<Sysname> system-view
# Switch to load balancing mode.
[Sysname] xbar load-balance
# Enable Full Mesh mode.
[Sysname] fullmesh-enhance enable
# Check whether Full Mesh mode is
activated.
[Sysname] display fullmesh-enhance
Configuration status: Enabled
Operation status: Active
