Adding new Nexus 2K fabric extender

This step by step on how to add new Nexus 2000 (N2K) to Nexus 5000 (N5K)

Before apply, issue command sh fex and sh interface fex, this will show you fex is connected, but not online

  FEX         FEX           FEX                       FEX              

Number    Description      State            Model            Serial    

------------------------------------------------------------------------

---       --------             Connected     N2K-C2248TP-1GE   JAF1453BPRB

Then check to which interface this fex is connected to, sh interface fex

     Fabric      Fabric       Fex                FEX          

Fex  Port      Port State    Uplink    Model         Serial   

---------------------------------------------------------------

---   Eth1/12    Discovered     1    N2K-C2248TP-1GE  JAF1453BPRB

1.create new Fex instant

-use fex-id range number between 100-199

-choose 10G Ethernet ports

 fex <fex-id>

  pinning max-links <1-4>

  description <des..>

2.create new port channel and vPC

Interface port-channel <id>

 description <des..>

 switchport mode fex-fabric

 vpc <vpc-id>

 fex associate <fex-id created above>

3.bind port to the PO created above

interface Ethernet1/9

  description <des...>

  fex associate <fex-id>

  switchport mode fex-fabric

  channel-group <PO-id>

Example.

once finish issue command sh fex again to make sure the new fabric extender is online (it'll download image from N5K before it become fully online, may take some time)

FEX         FEX           FEX                       FEX              

Number    Description      State            Model            Serial    

------------------------------------------------------------------------

112  aus-b3-gp4-l9-fex12                Online     N2K-C2248TP-1GE   JAF1453BPRB

Usually each N5K in Austin only server 1 vlan, in this case we can just assign all the new port in one shot

interface ethernet 112/1/1 - 48

  switchport access vlan 2015

  spanning-tree port type edge

  spanning-tree bpdufilter enable

Implementing QoS DSCP marking on customer router

In this scenario, QoS policing done on Provider CE router and customer don't have access to it, Customer only mark the traffic with DSCP value for QoS policing (on the CE router)

We'll classify highest priority voice to COS1, high priority traffic COS2, less priority COS4 and for traffic didn't match any of those class will be automatically set to COS3 (medium priority)

1.       Classify the packets using ACL, ACL 101 for COS1, 102 COS2  and 104 COS4(traffic didn't match any of the ACL will fall to default, COS3)

access-list 101 remark **** Global VoIP ranges *****

access-list 101 permit ip any 10.1.0.0 0.0.255.255

access-list 101 permit ip 10.1.0.0 0.0.255.255 any

access-list 101 remark **** Global Citrix ranges *****

access-list 101 permit ip any 10.2.0.0 0.0.255.255

access-list 101 permit ip 10.2.0.0 0.0.255.255 any

access-list 101 remark **** Global FTP ranges *****

access-list 101 permit ip any 10.4.0.0 0.0.255.255

access-list 101 permit ip 10.4.0.0 0.0.255.255 any

2.       Set class-map for each packets that match ACL above into respective class and give a name

class-map match-any COS4

  description Low priority data traffic match

match access-group 104

class-map match-any COS2

  description High priority data traffic match

match access-group 102

class-map match-any COS1

  description Highest priority real-time voice traffic

match access-group 101

3.       Create policy map and mark the DSCP value and bandwidth for each class-map

policy-map QoSMarking

class COS1

  set ip dscp ef

  priority 1536

class COS2

  set ip dscp af31

  bandwidth 4096

  random-detect dscp-based

class COS4

  set ip dscp default

  bandwidth 14336

class class-default

  set ip dscp af21

  bandwidth 18432

  random-detect dscp-based

4.       Apply policy map to interface Gi 0/1 that facing CE router

interface GigabitEthernet0/1

description External_facing_CE

ip address 10.9.9.1 255.255.255.252

service-policy output QoSMarking

Basically this is how it's work

·         Traffic entering LAN router from Customer LAN

·         Every packets routed to Gi0/1 will go thru the policy map marking process(step4)

·         First Policy-map will check the packet fall under which class(step3)

·         this done by class-map (step2)

·         by referring the ACL configure on each class(step1)

·         once found, the Policy-map will set the DSCP value base on class the packet belong to

·         If the packet didn't match any ACL, Policy-map will automatically set class-default to it (in this case COS3)