Hi, everyone! Today I’m going to introduce how to combining standalone switches into a CSS.

Networking Requirements

Two modular switches at the aggregation layer use VRRP and STP to implement gateway redundancy. To simplify the configuration, the two modular switches need to be combined into a single logical switch, called Cluster Switch System (CSS).

In Figure 1-1, S1 and S2 at the aggregation layer are two standalone switches and need to be combined into a CSS to simplify the configuration and facilitate maintenance and management.

Figure 1-1 Networking diagram of combining standalone switches into a CSS

When two standalone devices are combined into a CSS, major configuration changes include:

l The VRRP gateway redundancy protocol deployed at the aggregation layer is not required and its configuration needs to be deleted.

l The STP loop prevention protocol deployed at the access layer is not required and its configuration needs to be deleted.

l The links at the access, aggregation, and core layers are changed to Eth-Trunks, and related interface configurations need to be changed, including basic VLAN configuration, QoS configuration, and ACL configuration.

Guidelines

l This operation applies to CSS card clustering and service port clustering. Before combining two standalone switches into a CSS, ensure that the hardware and software of the two switches meet CSS requirements. For CSS card clustering, CSS cards and cluster cables have been prepared. For service port clustering, the service cards that support service port clustering and cluster cables have been prepared.

l After the CSS function is enabled on a standalone switch, configurations on the interfaces of the switch will be lost. Therefore, back up the configuration file before enabling the CSS function.

l The following procedure provides only the related configurations. Whether other configurations need to be changed depends on the actual networking.

Procedure

Step 1 In the original networking, traffic at the access layer is load-balanced among multiple links through STP and VRRP. In Figure 1-2, some traffic is forwarded through S1 and some traffic is forwarded through S2.

Figure 1-2 Existing traffic forwarding

Step 2 Manually shut down the uplink and downlink ports of S2 to change the STP status and VRRP status so that S2 is isolated from the network and all traffic is forwarded through S1, as shown in Figure 1-3.

Figure 1-3 Traffic forwarding after an STP and VRRP status switchover

Step 3 Back up the configuration file of S2. After a standalone switch has the CSS function enabled and restarts, the interface number format on the switch will be changed from slot ID/subcard ID/port number to stack member ID/slot ID/subcard ID/port number, and the configurations on the interfaces of the switch will be lost.

Step 4 Change S2 to the CSS mode.

l Procedure for configuring service port clustering

1. Power off S2, install service cards, and power on S2.

2. Configure the CSS connection mode and CSS priority on S2.

<S2> system-view
[S2] set css mode lpu
[S2] set css priority 200 // Set the CSS priority to 200 to make S2 become the CSS master. The default CSS priority is 100.

Current Id   Saved Id     CSS Enable   CSS Mode    Priority    Master Force
------------------------------------------------------------------------------
1            1            Off          LPU         200         On

[S2] display css status saved // Check whether the configuration is correct.

3. Configure service ports as CSS ports. For example, configure service ports XGE1/0/1, XGE1/0/2, XGE2/0/1, and XGE2/0/2 as CSS ports.

[S2] interface css-port 1
[S2-css-port1] port interface xgigabitethernet 1/0/1 to xgigabitethernet 1/0/2 enable
[S2-css-port1] quit
[S2] interface css-port 2
[S2-css-port2] port interface xgigabitethernet 2/0/1 to xgigabitethernet 2/0/2 enable
[S2-css-port2] quit

4. Enable the CSS function on S2 and restart S2.

[S2] css enable
Warning: The CSS configuration will take effect only after the system is rebooted. The next CSS mode is LPU. Reboot now? [Y/N]:y

5. After S2 is restarted, check its CSS status. If the command output similar to the following is displayed, S2 has been changed to the CSS mode.

<S2> display device
Chassis 1 (Master Switch)
S9706's Device status:
Slot Sub Type         Online Power      Register       Status     Role
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
1     - EH1D2X12SSA0 Present PowerOn Registered     Normal     NA
2     - EH1D2X12SSA0 Present PowerOn Registered     Normal     NA
3     - EH1D2S04SX1E Present PowerOn Registered     Normal     NA
4     - EH1D2S04SX1E Present PowerOn Registered     Normal     NA
7     - EH1D2SRUC000 Present PowerOn Registered     Normal     Master
8     - EH1D2SRUC000 Present PowerOn Registered     Normal     Slave
PWR1 - -            Present PowerOn Registered     Normal     NA
PWR2 - -           Present -       Unregistered   -          NA
CMU2 - EH1D200CMU00 Present PowerOn Registered     Normal     Master
FAN1 - -            Present PowerOn Registered     Abnormal   NA
FAN2 - -            Present -       Unregistered   -          NA

l Procedure for configuring CSS card clustering

1. Power off S2, install CSS cards, and power on S2.

2. Configure the CSS priority on S2.

<S2> system-view
[S2] set css priority 200 // Set the CSS priority to 200 to make S2 become the CSS master. The default CSS priority is 100.

Current Id   Saved Id     CSS Enable   CSS Mode    Priority    Master Force
------------------------------------------------------------------------------
1            1            Off          CSS card    200         On

[S2] display css status saved // Check whether the configuration is correct.

3. Enable the CSS function on S2 and restart S2.

[S2] css enable
Warning: The CSS configuration will take effect only after the system is rebooted. The next CSS mode is CSS card. Reboot now? [Y/N]:y

4. After S2 is restarted, check its CSS status. If the command output similar to the following is displayed, S2 has been changed to the CSS mode (a single-chassis cluster CSS-1).

<S2> display device
Chassis 1 (Master Switch)
S9706's Device status:
Slot Sub Type         Online Power      Register       Status     Role
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
3     - EH1D2S04SX1E Present PowerOn Registered     Normal     NA
4     - EH1D2S04SX1E Present PowerOn Registered     Normal     NA
7     - EH1D2SRUC000 Present PowerOn Registered     Normal     Master
1     - EH1D2VS08000 Present PowerOn Registered     Normal     NA
8     - EH1D2SRUC000 Present PowerOn Registered     Normal     Slave
      1 EH1D2VS08000 Present PowerOn Registered     Normal    NA
PWR1 - -            Present PowerOn Registered     Normal     NA
PWR2 - -            Present -       Unregistered   -          NA
CMU2 - EH1D200CMU00 Present PowerOn Registered     Normal     Master
FAN1 - -            Present PowerOn Registered     Abnormal   NA
FAN2 - -            Present -       Unregistered   -          NA

Step 5 Change the configuration of S2. Alternatively, change the configuration after S1 and S2 are combined into a CSS. Changing the configuration of S2 before S1 and S2 are combined into a CSS can reduce the traffic loss.

Figure 1-4 Single-chassis CSS

l Bundle uplink ports XGE1/4/0/1 and XGE1/4/0/2 of CSS-1 into an Eth-Trunk and perform the same configurations as these uplink ports on the Eth-Trunk.

Assume that the configurations on the uplink ports (connecting CSS-1 to switches at the core layer) are as follows:

#
interface XGigabitEthernet4/0/1
undo portswitch
ip address 192.168.4.2 255.255.255.0
#
interface XGigabitEthernet4/0/2
port link-type trunk
port trunk allow-pass vlan 100 200
#

Change the configuration of S2.

<S2> system-view
[S2] sysname CSS // Change the device name to facilitate maintenance.
[CSS] interface eth-trunk 20 // Add the port connecting the CSS to one core switch to Eth-Trunk 20.
[CSS-Eth-Trunk20] trunkport xgigabitethernet1/4/0/1
[CSS-Eth-Trunk20] ip address 192.168.4.2 255.255.255.0
[CSS-Eth-Trunk20] quit
[CSS] interface eth-trunk 10 // Add the port connecting the CSS to the other core switch to Eth-Trunk 10.
[CSS-Eth-Trunk10] trunkport xgigabitethernet1/4/0/2
[CSS-Eth-Trunk10] port link-type trunk
[CSS-Eth-Trunk10] port trunk allow-pass vlan 100 200
[CSS-Eth-Trunk10] quit

l Change the configurations of switches at the core layer and access layer and bundle physical ports into Eth-Trunks. The procedure is similar to the preceding procedure.

l Delete the VRRP configuration on CSS-1.

Assume that the configurations of VLANIF interfaces are as follows:

#
interface Vlanif100
ip address 10.1.10.1 255.255.255.0
vrrp vrid 1 virtual-ip 10.1.10.111
vrrp vrid 1 priority 120
#
interface Vlanif200
ip address 10.1.20.1 255.255.255.0
vrrp vrid 2 virtual-ip 10.1.20.111
#

Delete the configurations of VLANIF interfaces.

[CSS] interface vlanif 100
[CSS-Vlanif100] undo vrrp vrid 1
[CSS-Vlanif100] undo ip address
[CSS-Vlanif100] quit
[CSS] interface vlanif 200
[CSS-Vlanif200] undo vrrp vrid 2
[CSS-Vlanif200] undo ip address
[CSS-Vlanif200] quit

1. Delete unnecessary network segments from the OSPF routing domain.

2. Change the configurations of the interfaces on which QoS and ACLs are configured to bundle these interfaces into Eth-Trunks.

3. Change the STP priority of CSS-1 so that CSS-1 becomes the root switch of all VLANs.

Step 6 Run the undo shutdown command to disable the interfaces on CSS-1 to check whether Layer 2 and Layer 3 forwarding between CSS-1 and switches at the access layer and core layer is normal.

Step 7 After confirming that Layer 2 and Layer 3 forwarding between CSS-1 and switches at the access layer and core layer is normal, shut down interfaces on S1 so that S1 is isolated from the network and all traffic is forwarded through CSS-1.

Figure 1-5 Traffic switching to CSS-1

Step 8 Change S1 to the CSS mode. After S1 is added to CSS-1, S1 uses the configuration file of CSS-1.

l Procedure for configuring service port clustering

1. Power off S1, install service cards, connect the cluster cables between S1 and CSS-1, and power on S1.

2. Configure the CSS connection mode and CSS ID and retain the default CSS priority 100 on S1.

<S1> system-view
[S1] set css mode lpu
[S1] set css id 2
[S1] display css status saved // Check whether the configuration is correct.
Current Id   Saved Id     CSS Enable   CSS Mode    Priority    Master Force
------------------------------------------------------------------------------
1            2            Off          LPU         100         On

3. Configure service ports as CSS ports. For example, configure service ports XGE1/0/1, XGE1/0/2, XGE2/0/1, and XGE2/0/2 as CSS ports.

[S1] interface css-port 1
[S1-css-port1] port interface xgigabitethernet 1/0/1 to xgigabitethernet 1/0/2 enable
[S1-css-port1] quit
[S1] interface css-port 2
[S1-css-port2] port interface xgigabitethernet 2/0/1 to xgigabitethernet 2/0/2 enable
[S1-css-port2] quit

4. Enable the CSS function on S1 and restart S1.

[S1] css enable
Warning: The CSS configuration will take effect only after the system is rebooted. The next CSS mode is LPU. Reboot now? [Y/N]:y

5. After S1 is restarted, check its CSS status. If the command output similar to the following is displayed, S1 has joined the CSS.

<CSS> display device
Chassis 1 (Master Switch)
S9706's Device status:
Slot Sub Type         Online Power      Register       Status     Role
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
1     - EH1D2X12SSA0 Present PowerOn Registered     Normal     NA
2     - EH1D2X12SSA0 Present PowerOn Registered     Normal     NA
3     - EH1D2S04SX1E Present PowerOn Registered     Normal     NA
4     - EH1D2S04SX1E Present PowerOn Registered     Normal     NA
7     - EH1D2SRUC000 Present PowerOn Registered     Normal     Master
8     - EH1D2SRUC000 Present PowerOn Registered     Normal     Slave
PWR1 - -            Present PowerOn Registered     Normal     NA
PWR2 - -            Present -       Unregistered   -          NA
CMU2 - EH1D200CMU00 Present PowerOn Registered     Normal     Master
FAN1 - -            Present PowerOn Registered     Abnormal   NA
FAN2 - -            Present -       Unregistered   -          NA
Chassis 2 (Standby Switch)
S9706's Device status:
Slot Sub Type         Online Power      Register       Status     Role
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
1     - EH1D2X12SSA0 Present PowerOn Registered     Normal     NA
2     - EH1D2X12SSA0 Present PowerOn Registered     Normal     NA
3     - EH1D2S04SX1E Present PowerOn Registered     Normal     NA
4     - EH1D2S04SX1E Present PowerOn Registered     Normal     NA
7     - EH1D2SRUC000 Present PowerOn Registered     Normal     Master
8     - EH1D2SRUC000 Present PowerOn Registered     Normal     Slave
PWR1 - -            Present PowerOn Registered     Normal     NA
PWR2 - -            Present -       Unregistered   -          NA
CMU2 - EH1D200CMU00 Present PowerOn Registered    Normal     Master
FAN1 - -            Present PowerOn Registered     Abnormal   NA
FAN2 - -            Present -       Unregistered   -          NA

l Procedure for configuring CSS card clustering

1. Power off S1, install CSS cards, connect the cluster cables between S1 and CSS-1, and power on S1.

2. Configure the CSS ID and retain the default CSS priority 100 on S1.

<S1> system-view
[S1] set css id 2

3. Enable the CSS function on S1 and restart S1.

[S1] css enable
Warning: The CSS configuration will take effect only after the system is rebooted. The next CSS mode is CSS card. Reboot now? [Y/N]:y

4. After S1 is restarted, check its CSS status. If the command output similar to the following is displayed, S1 has joined the CSS.

<CSS> display device
Chassis 1 (Master Switch)
S9706's Device status:
Slot Sub Type         Online Power      Register       Status     Role
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
3     - EH1D2S04SX1E Present PowerOn Registered     Normal     NA
4     - EH1D2S04SX1E Present PowerOn Registered     Normal     NA
7     - EH1D2SRUC000 Present PowerOn Registered     Normal     Master
      1 EH1D2VS08000 Present PowerOn Registered     Normal     NA
8     - EH1D2SRUC000 Present PowerOn Registered     Normal     Slave
      1 EH1D2VS08000 Present PowerOn Registered     Normal     NA
PWR1 - -            Present PowerOn Registered     Normal     NA
PWR2 - -            Present -       Unregistered   -          NA
CMU2 - EH1D200CMU00 Present PowerOn Registered     Normal     Master
FAN1 - -            Present PowerOn Registered     Abnormal   NA
FAN2 - -            Present -       Unregistered   -          NA
Chassis 2 (Standby Switch)
S9706's Device status:
Slot Sub Type         Online Power      Register       Status     Role
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
3     - EH1D2S04SX1E Present PowerOn Registered     Normal     NA
4     - EH1D2S04SX1E Present PowerOn Registered     Normal     NA
7     - EH1D2SRUC000 Present PowerOn Registered     Normal     Master
      1 EH1D2VS08000 Present PowerOn Registered     Normal     NA
8     - EH1D2SRUC000 Present PowerOn Registered     Normal     Slave
      1 EH1D2VS08000 Present PowerOn Registered     Normal     NA
PWR1 - -            Present PowerOn Registered     Normal     NA
PWR2 - -            Present -       Unregistered   -          NA
CMU2 - EH1D200CMU00 Present PowerOn Registered     Normal     Master
FAN1 - -            Present PowerOn Registered     Abnormal   NA
FAN2 - -            Present -       Unregistered   -          NA

Step 9 S1 has become CSS-2 (CSS standby).

Figure 1-6 Two CSS systems merging into one

Step 10 Change the configuration of CSS-2 and add interfaces of CSS-2 to Eth-Trunks.

l Add uplink ports XGE2/4/0/1 and XGE2/4/0/2 of CSS-2 to Eth-Trunks.

[CSS] interface eth-trunk 20
[CSS-Eth-Trunk20] trunkport xgigabitethernet2/4/0/1
[CSS-Eth-Trunk20] quit
[CSS] interface eth-trunk 10
[CSS-Eth-Trunk10] trunkport xgigabitethernet2/4/0/2
[CSS-Eth-Trunk10] quit

1. Change the configurations of switches at the core layer and access layer and bundle physical ports into Eth-Trunks. The procedure is similar to the preceding procedure.

Step 11 Run the undo shutdown command to disable the interfaces of CSS-2 and check whether Layer 2 and Layer 3 forwarding between CSS-2 and switchesat the core layer and access layer is normal. In this case, S1 and S2 have been combined into a CSS, as shown in Figure 1-7

Figure 1-7 Traffic forwarding after a CSS merge