VSS是思科的一种交换机集群技术,可将两台物理交换机虚拟成一台逻辑交换机。两台物理交换机通过VSL链路连接,用于承载控制平面和转发平面流量。本文以两台Catalyst 4500为例,展示如何配置VSS。
名词:
VSS – Virtual Switching System
VSL – Virtual Switch Link
配置步骤:
1. 配置Virtual Switch Domain和Switch Numbers
首先,您须在 VSS 的两台交换机上配置相同的Virtual Switch Domain。Virtual Switch Domain是1到255之间的数字。然后您须将一台交换机配置为Switch Number 1,另一台交换机配置为Switch Number 2。
SW1#conf t
Enter configuration commands, one per line. End with CNTL/Z.
SW1(config)#switch virtual domain 10
Domain ID 10 config will take effect only
after the exec command 'switch convert mode virtual' is issued
SW1(config-vs-domain)#switch 1
SW1(config-vs-domain)#exit
SW1(config)#
SW2#conf t
Enter configuration commands, one per line. End with CNTL/Z.
SW2(config)#switch virtual domain 10
Domain ID 10 config will take effect only
after the exec command 'switch convert mode virtual' is issued
SW2(config-vs-domain)#switch 2
SW2(config-vs-domain)#exit
SW2(config)#
2. 配置VSL PortChannel
您需要在每台交换机上使用PortChannel配置 VSL。PortChannel号需要不一样,否则VSS不能正常建立将进入 RPR 模式。为避免这种情况,请为两个交换机上的两个PortChannel分配不同编号。
SW1(config)#int port-channel 5
SW1(config-if)#switchport
SW1(config-if)#switch virtual link 1
SW1(config-if)#no shut
SW1(config-if)#exit
*Jan 24 05:19:57.092: %SPANTREE-6-PORTDEL_ALL_VLANS: Port-channel5 deleted from all Vlans
SW2(config)#int port-channel 10
SW2(config-if)#switchport
SW2(config-if)#switch virtual link 2
SW2(config-if)#no shut
SW2(config-if)#exit
SW2(config)#
*Jan 24 05:14:17.273: %SPANTREE-6-PORTDEL_ALL_VLANS: Port-channel10 deleted from all Vlans
3. 配置VSL端口
将 VSL 物理端口添加到PortChannel。在以下示例中,Switch 1上的Gi7/3和Gi7/4接口连接到Switch 2上的Gi4/45和Gi4/46接口。
SW1(config)#int range gig7/3 - 4
SW1(config-if-range)#switchport mode trunk
SW1(config-if-range)#channel-group 5 mode on
WARNING: Interface GigabitEthernet7/3 placed in restricted config mode. All extraneous configs removed!
WARNING: Interface GigabitEthernet7/4 placed in restricted config mode. All extraneous configs removed!
SW1(config-if-range)#exit
SW2(config)#int range gig4/45 - 46
SW2(config-if-range)#switchport mode trunk
SW2(config-if-range)#channel-group 10 mode on
WARNING: Interface GigabitEthernet4/45 placed in restricted config mode. All extraneous configs removed!
WARNING: Interface GigabitEthernet4/46 placed in restricted config mode. All extraneous configs removed!
SW2(config-if-range)#exit
注意:一旦使用“channel-group”命令将接口放入VSL端口通道,则接口进入“notconnect”状态。Interface status显示为UP,但line protocol将down。接口将处于up/down状态,直到交换机在步骤 4 中重新启动。
4. 切换交换机至Virtual Switch模式
在switch 1上输入switch convert mode virtual
命令将交换机转换为 Virtual Switch模式。系统创建一个转换后的配置文件,并将配置文件保存到bootflash,并自动重启。
SW1#switch convert mode virtual
This command will convert all interface names
to naming convention "interface-type switch-number/slot/port",
save the running config to startup-config and
reload the switch.
Do you want to proceed? [yes/no]: yes
Converting interface names
Building configuration...
Compressed configuration from 6551 bytes to 2893 bytes[OK]
Saving converted configuration to bootflash: ...
Destination filename [startup-config.converted_vs-20130124-062921]?
Please stand by while rebooting the system...
Restarting system.
Rommon (G) Signature verification PASSED
Rommon (P) Signature verification PASSED
FPGA (P) Signature verification PASSED
同样的操作命令将switch 2转换为Virtual Switch模式:
SW2#switch convert mode virtual
This command will convert all interface names
to naming convention "interface-type switch-number/slot/port",
save the running config to startup-config and
reload the switch.
Do you want to proceed? [yes/no]: yes
Converting interface names
Building configuration...
Compressed configuration from 6027 bytes to 2774 bytes[OK]
Saving converted configuration to bootflash: ...
Destination filename [startup-config.converted_vs-20130124-052526]?
Please stand by while rebooting the system...
Restarting system.
Rommon (G) Signature verification PASSED
Rommon (P) Signature verification PASSED
FPGA (P) Signature verification PASSED
重启完毕后交换机将处于Virtual Switch模式,可以通过如下命令验证。
show switch virtual
查询virtual switch domain number和switch number及角色(Active or Standby)。
SW1#sh switch virtual
Executing the command on VSS member switch role = VSS Active, id = 1
Switch mode : Virtual Switch
Virtual switch domain number : 10
Local switch number : 1
Local switch operational role: Virtual Switch Active
Peer switch number : 2
Peer switch operational role : Virtual Switch Standby
Executing the command on VSS member switch role = VSS Standby, id = 2
Switch mode : Virtual Switch
Virtual switch domain number : 10
Local switch number : 2
Local switch operational role: Virtual Switch Standby
Peer switch number : 1
Peer switch operational role : Virtual Switch Active
- Standby Switch用console登录后无法查看和修改配置,仅能看到如下提示:
SW2-standby>
Standby console disabled
show switch virtual role'
查看交换机详细角色信息:
SW1#sh switch virtual role
Executing the command on VSS member switch role = VSS Active, id = 1
RRP information for Instance 1
--------------------------------------------------------------------
Valid Flags Peer Preferred Reserved
Count Peer Peer
--------------------------------------------------------------------
TRUE V 1 1 1
Switch Switch Status Preempt Priority Role Local Remote
Number Oper(Conf) Oper(Conf) SID SID
--------------------------------------------------------------------
LOCAL 1 UP FALSE(N ) 100(100) ACTIVE 0 0
REMOTE 2 UP FALSE(N ) 100(100) STANDBY 6834 6152
Peer 0 represents the local switch
Flags : V - Valid
In dual-active recovery mode: No
Executing the command on VSS member switch role = VSS Standby, id = 2
RRP information for Instance 2
--------------------------------------------------------------------
Valid Flags Peer Preferred Reserved
Count Peer Peer
--------------------------------------------------------------------
TRUE V 1 1 1
Switch Switch Status Preempt Priority Role Local Remote
Number Oper(Conf) Oper(Conf) SID SID
--------------------------------------------------------------------
LOCAL 2 UP FALSE(N ) 100(100) STANDBY 0 0
REMOTE 1 UP FALSE(N ) 100(100) ACTIVE 6152 6834
Peer 0 represents the local switch
Flags : V - Valid
In dual-active recovery mode: No
show switch virtual link
查看VSL链路状态:
SW1#sh switch virtual link
Executing the command on VSS member switch role = VSS Active, id = 1
VSL Status : UP
VSL Uptime : 3 minutes
VSL Control Link : Gi1/7/4
Executing the command on VSS member switch role = VSS Standby, id = 2
VSL Status : UP
VSL Uptime : 3 minutes
VSL Control Link : Gi2/4/45
show switch virtual link port-channel
查看PortChannel信息:
SW1#sh switch virtual link port-channel
Executing the command on VSS member switch role = VSS Active, id = 1
Flags: D - down P - bundled in port-channel
I - stand-alone s - suspended
H - Hot-standby (LACP only)
R - Layer3 S - Layer2
U - in use N - not in use, no aggregation
f - failed to allocate aggregator
M - not in use, no aggregation due to minimum links not met
m - not in use, port not aggregated due to minimum links not met
u - unsuitable for bundling
d - default port
w - waiting to be aggregated
Group Port-channel Protocol Ports
------+-------------+-----------+-------------------
5 Po5(SU) - Gi1/7/3(P) Gi1/7/4(P)
10 Po10(SU) - Gi2/4/45(P) Gi2/4/46(P)
Executing the command on VSS member switch role = VSS Standby, id = 2
Flags: D - down P - bundled in port-channel
I - stand-alone s - suspended
H - Hot-standby (LACP only)
R - Layer3 S - Layer2
U - in use N - not in use, no aggregation
f - failed to allocate aggregator
M - not in use, no aggregation due to minimum links not met
m - not in use, port not aggregated due to minimum links not met
u - unsuitable for bundling
d - default port
w - waiting to be aggregated
Group Port-channel Protocol Ports
------+-------------+-----------+-------------------
5 Po5(SU) - Gi1/7/3(P) Gi1/7/4(P)
10 Po10(SU) - Gi2/4/45(P) Gi2/4/46(P)
VSS正常运作后,交换机端口号由原来的Gi x/x自动转换成了Gi 1/x/x或Gi 2/x/x。1和2为两台硬件交换机编号,从逻辑上你可以把这两台交换机当作一台交换机了。你可以分别在这两台交换机上选一个端口比如Gi1/0/8和Gi2/0/8与其它交换机建立PortChannel。