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Verifying EPG,Fabric and hardware VLAN mapping

The below commands show the various VLAN's used in the fabric and the mapping between VLAN's

VLAN's allocated to Bridge Domain (BD)  and End Point Group (EPG) can be seen using 'show vlan'. esx_bd2 and esx_epg2 are used as examples in this document.

leaf101# show vlan

 VLAN Name                             Status    Ports
 ---- -------------------------------- --------- -------------------------------
 13   --                               active    Eth1/1, Eth1/3
 16   aci-demo:aci-demo-bd             active    Eth1/7
 17   aci-demo:aci-demo-applicatoin    active    Eth1/7
 18   aci-demo:aci-demo-applicatoin    active    Eth1/7
 28   poaniker:esx_bd2                 active    Eth1/25--------------28 is the BD vlan for esx_bd2 in tenant poaniker
 29   poaniker:esx_vmm:esx_epg2        active    Eth1/25-----------29 is the FD vlan for esx_epg2 in tenant poaniker

 VLAN Type  Vlan-mode
 ---- ----- ----------
 13   enet  CE
 16   enet  CE
 17   enet  CE
 18   enet  CE
 28   enet  CE
 29   enet  CE

The mappings between the access encap and internal VLAN for EPG and EPG to BD VLAN can be obtained by connecting to the module using vsh_lc

leaf101# vsh_lc
dns: l3vm_api_init failed
dns: l3vm_api_init failed

module-1# show system internal eltmc info vlan brief
VlanId  HW_VlanId Type            Access_enc Access_enc Fabric_enc Fabric_enc BDVlan
                                  Type                 Type
     13       19    BD_CTRL_VLAN    802.1q      4093     VXLAN  16777209       0
     16       22         BD_VLAN   Unknown         0     VXLAN  16547722      16
     17       23         FD_VLAN    802.1q       301     VXLAN      8193      16
     18       24         FD_VLAN    802.1q       300     VXLAN      8192      16
     28       20         BD_VLAN   Unknown         0     VXLAN  15695748      28
     29       21         FD_VLAN    802.1q       315     VXLAN      8207      28


The highlighted text corresponds to the example used in the output of 'show vlan'. The signifcance of each vlan is as follows:

315 is EPG encap vlan, used by the end host to send traffic
29 is the FD/internal vlan for EPG,should be same as seen in the 'show vlan' output. Each access_enc vlan has a FD_VLAN.
21 is the HW VLAN for the EPG, can also be checked in BCM HW
28 is the BD vlan associated to the FD vlan 29. If the BD has a subnet associated to it, the SVI for the BD corresponds to the BD VLAN. In this example, the SVI is interface vlan28 The end host default gateway is the IP address of interface  vlan 28.

leaf101# show interface vlan 28
Vlan28 is up, line protocol is up
  Hardware EtherSVI, address is  0022.bdf8.19ff
  Internet Address is
  MTU 9000 bytes, BW 10000000 Kbit, DLY 1 usec
   reliability 255/255, txload 1/255, rxload 1/255
  Carrier delay is 10 sec
  Encapsulation ARPA, loopback not set
  Keepalive not supported
  ARP type: ARPA
  Last clearing of "show interface" counters never
  30 seconds input rate 0 bits/sec, 0 packets/sec
  30 seconds output rate 0 bits/sec, 0 packets/sec
  Load-Interval #2: 5 minute (300 seconds)
    input rate 0 bps, 0 pps; output rate 0 bps, 0 pps
  L3 Switched:
    input: 0 pkts, 0 bytes - output: 0 pkts, 0 bytes
  L3 in Switched:
    ucast: 0 pkts, 0 bytes - mcast: 0 pkts, 0 bytes
  L3 out Switched:
    ucast: 0 pkts, 0 bytes - mcast: 0 pkts, 0 bytes


Checking VLAN translation in BCM shell

leaf101# vsh_lc
dns: l3vm_api_init failed
dns: l3vm_api_init failed

module-1# bcm-shell
bcm shell path: /lc/isan/bin/bcm-shell-hw
unit is 0
Available Unit Numbers: 0

bcm-shell.0> search vlan_xlate old_vlan_id=0x13B------convert access_enc vlan to hex, 315 in hex is 13B
Searching VLAN_XLATE table indexes 0x0 through 0x3fff...


Relevant output shown below:


VLAN_ID=0x13b = 315 in decimal
XLATE:NEW_VLAN_ID=0x15 =21 in decimal, which is the same as the HW VLAN in the output of 'show vlan'

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‎08-18-2014 08:47 PM
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