Create a Dual-Switch Configuration

This example shows how to create an SLB-L2 dual-switch configuration. Repeat steps 1 through 3 on both switches.

1. Shut down the ingress port and all server ports.

   SEFOS# configure terminal
   SEFOS(config)# interface extreme-ethernet 0/1
   SEFOS(config-if)# shutdown
   SEFOS(config-if)# exit
   SEFOS(config)# interface range extreme-ethernet 0/15-18
   SEFOS(config-if-range)# shutdown
   SEFOS(config-if-range)# exit

2. Disable GVRP and GMRP.

   SEFOS(config)# set gvrp disable
   SEFOS(config)# set gmrp disable

3. Form an LBG.

   SEFOS(config)# slb l2 1 extreme-ethernet 0/15-18
   SEFOS(config-if-range)# exit

4. View the configuration.

   SEFOS# show slb l2
    
   L2 SLB Group #1
   Failover Method: Failover to Standby Port(s) first, then All Ports
   Port Members:
   Port   State     Comments
   ====   =====     =================
    15    IDLE
    16    IDLE
    17    IDLE
    18    IDLE

   The same output will appear from group 2 after you run these commands on switch 2.

   All ports are in idle state because the interface ports 15 through 18 are still disabled.

5. Set the LBG failover method (if different from the default).

   SEFOS(config)# slb l2 failover-method 1 prefer-standby

6. Set the load distribution hash policy.

   To get forward and reverse traffic to be hashed to the same node (referred to as hash symmetry), you must choose a policy that includes the sym option. Use either of the following methods to maintain hash symmetry.

   This example includes both source and destination IP addresses for hashing in a symmetrical manner. The same hash results even if the source and destination IP addresses are swapped.

   SEFOS(config)# slb l2 policy src-ip dest-ip sym

   Alternatively, you could maintain hash symmetry while using only the src-ip field on switch A and dest-ip field on switch B.

   On switch A, type.

   SEFOS(config)# slb l2 policy src-ip sym

   On switch B, type.

   SEFOS(config)# slb l2 policy dest-ip sym

7. Set up the bump-in-the-wire configuration.

   To set up the bump-in-the-wire configuration, you must use a VLAN tag to identify ingress and egress traffic ports. This example associates the LBG and the ingress/egress port with VLAN 2. The following steps set up VLAN membership for the ports that participate in the LBG and also set up the switch to insert the VLAN TAG to outgoing packets from port 15-18.

   1. Set up VLAN.

      SEFOS(config)# vlan 2
      SEFOS(config-vlan)# port extreme-ethernet 0/15-18
      SEFOS(config-if-range)# exit

   2. Set up VLAN membership and PVID for the ingress port.

      SEFOS(config)# interface extreme-ethernet 0/1
      SEFOS(config-if)# switchport access vlan 2
      SEFOS(config-if)# exit

   3. View the configuration.

      SEFOS# show vlan
       
      Vlan database
      -------------
      Vlan ID            : 1
      Member Ports       : Ex0/2, Ex0/3, Ex0/4, Ex0/5, Ex0/6, Ex0/7
                           Ex0/8, Ex0/9, Ex0/10, Ex0/11, Ex0/12, Ex0/13
                           Ex0/14, Ex0/15, Ex0/16, Ex0/17, Ex0/18, Ex0/19
                           Ex0/20, Ex0/21, Ex0/22, Ex0/23, Ex0/24
      Untagged Ports      : Ex0/2, Ex0/3, Ex0/4, Ex0/5, Ex0/6, Ex0/7
                           Ex0/8, Ex0/9, Ex0/10, Ex0/11, Ex0/12, Ex0/13
                           Ex0/14, Ex0/15, Ex0/16, Ex0/17, Ex0/18, Ex0/19
                           Ex0/20, Ex0/21, Ex0/22, Ex0/23, Ex0/24
      Forbidden Ports     : None
      Name                :
      Status              : Permanent
      -------------
      Vlan ID             : 2
      Member Ports        : Ex0/1, Ex0/15, Ex0/16, Ex0/17, Ex0/18
      Untagged Ports      : Ex0/1
      Forbidden Ports     : None
      Name                :
      Status              : Permanent
      ----------------------------------------------------

8. Set up ACL.
   1. Set up ACL rules in the ingress port such that the permitted traffic is forwarded to the LBG.

      In this example, all packets with a source IP address of 1.2.3.4 are redirected to LBG group 1, which was set up in the preceding steps. All other packets will be denied access by the ingress port.

      SEFOS(config)# ip access-list extended 20
      SEFOS(config-ext-nacl)# permit ip any any loadbalance 1
      SEFOS(config-ext-nacl)# exit
      SEFOS(config)# interface extreme-ethernet 0/1
      SEFOS(config-if)# ip access-list 20 in
      SEFOS(config-if)# exit

   2. Steer the packets to the egress port.

      All packets arriving the switch ports from the servers within the LBG need to be steered to the egress port. In this example, the processed packets are steered from the servers back to same switch port used as the ingress port.

      SEFOS(config)# mac access-list extended 21
      SEFOS(config-ext-macl)# permit any any vlan 2 redirectport extreme-ethernet 0/1
      SEFOS(config-ext-macl)# exit
      SEFOS(config)# mac access-list extended 91
      SEFOS(config-ext-macl)# deny any any
      SEFOS(config-ext-macl)# exit
      SEFOS(config)# interface range extreme-ethernet 0/15-18
      SEFOS(config-if-range)# mac access-list 21 in
      SEFOS(config-if-range)# mac access-list 91 in
      SEFOS(config-if-range)# end

   3. View the ACL.

      SEFOS# show access-list
       
      Extended IP Access List 20
      -----------------------------
      Filter Priority                  : 1
      Filter Protocol Type             : ANY
      IP address Type                  : IPV4
      Source IP address                : 0.0.0.0
      Source IP address mask           : 0.0.0.0
      Source IP Prefix Length          : 0
      Destination IP address           : 0.0.0.0
      Destination IP address mask      : 0.0.0.0
      Destination IP Prefix Length     : 0
      Flow Identifier                  : 0
      In Port List                     : Ex0/1
      Out Port List                    : NIL
      Filter TOS                       : NIL
      Filter DSCP                      : NIL
      Filter Action                    : Load balance to Group 1
      Status                           : Active
       
      Extended IP Access List 90
      -----------------------------
      Filter Priority                  : 1
      Filter Protocol Type             : ANY
      IP address Type                  : IPV4
      Source IP address                : 0.0.0.0
      Source IP address mask           : 0.0.0.0
      Source IP Prefix Length          : 0
      Destination IP address           : 0.0.0.0
      Destination IP address mask      : 0.0.0.0
      Destination IP Prefix Length     : 0
      Flow Identifier                  : 0
      In Port List                     : Ex0/1
      Out Port List                    : NIL
      Filter TOS                       : NIL
      Filter DSCP                      : NIL
      Filter Action                    : Deny
      Status                           : Active
       
      MAC ACCESS LISTS
      -----------------
       
      Extended MAC Access List 21
      -----------------------------
      Filter Priority                  : 1
      Ether Type                       : 0
      Protocol Type                    : 0
      Vlan Id                          : 2
      User-Priority                    : 0
      Destination MAC Address          : 00:00:00:00:00:00
      Source MAC Address               : 00:00:00:00:00:00
      In Port List                     : Ex0/15 , Ex0/16 , Ex0/17 , Ex0/18
      Filter Action                    : Redirect to Port 1
      Status                           : Active
       
      Extended MAC Access List 91
      -----------------------------
      Filter Priority                  : 1
      Ether Type                       : 0
      Protocol Type                    : 0
      Vlan Id                          : 0
      User-Priority                    : 0
      Destination MAC Address          : 00:00:00:00:00:00
      Source MAC Address               : 00:00:00:00:00:00
      In Port List                     : Ex0/15 , Ex0/16 , Ex0/17 , Ex0/18
      Filter Action                    : Deny
      Status                           : Active

9. Enable the switch ports.

   SEFOS(config)# interface range extreme-ethernet 0/15-18
   SEFOS(config-if-range)# no shutdown
   SEFOS(config-if-range)# exit
   SEFOS(config)# interface extreme-ethernet 0/1
   SEFOS(config-if)# no shutdown
   SEFOS(config-if)# end

10. View the SLB-L2 configuration.

    SEFOS# show slb l2
     
    L2 SLB Group #1
    Failover Method: Failover to Standby Port(s) first, then All Ports
    Port Members:
    Port   State     Comments
    ====   =====     =================
     15    ACTIVE
     16    ACTIVE
     17    ACTIVE
     18    ACTIVE

    It might take up to 30 seconds for the port status to show. If executing the slb show command does not show the port status, try again in intervals of a few seconds until the status displays. If no status appears after 30 seconds, ensure that you have correctly completed the preceding steps.

    For information about the status of a server member, see Conditions for a Member Participating in Load Distribution.

11. Save the current configuration (if needed).

    SEFOS# write startup-config