First foray into Cisco Nexus gear
Posted on September 23, 2016
We’ve just some Nexus 3548-X switches and being my first hands on experience with these devices this post will serve as a small notebook of things I’ve deemed worth jotting down.
Interface Naming and Status
The first thing which stood out was that all interfaces are named Ethernet
.
As these switches are populated with SFP+ ports, it no longer makes sense to
call a port FastEthernet 1/1
or GigabitEthernet 1/1
since the port speed
will depend on the SFP+ module used. It is also worth noting that a 10Gbps
SFP+ will only permit 10Gbps connectivity - you cannot connect a 10Gbps SFP+
to a GigabitEthernet port/SFP and have it negotiate down to 1Gbps.
Another difference is that show ip int brief
will only show layer 3
interfaces (including SVIs) under NX-OS.
switch(config)# show ip int brief
IP Interface Status for VRF "default"(1)
Interface IP Address Interface Status
Vlan10 1.1.1.1 protocol-down/link-down/admin-down
To show the status of all interfaces, show int brief
can be used. This
command is also useful as it shows the VLAN and reason for the interface
status - eg, an SFP not being present.
switch(config)# show int brief
--------------------------------------------------------------------------------
Ethernet VLAN Type Mode Status Reason Speed Port
Interface Ch #
--------------------------------------------------------------------------------
Eth1/1 1 eth access down SFP not inserted 10G(D) --
Eth1/2 1 eth access down SFP not inserted 10G(D) --
Eth1/3 1 eth access down SFP not inserted 10G(D) --
Eth1/4 1 eth access down SFP not inserted 10G(D) --
Eth1/5 1 eth access down Link not connected 10G(D) --
Nexus Features
NX-OS modular, meaning many features, or modules are disabled by default. For
example, if SVIs are required, the interface-vlan
must be enabled. Otherwise
the command will be rejected.
switch(config)# int vlan 10
^
Invalid interface format at '^' marker.
switch(config)# feature interface-vlan
switch(config)# int vlan 10
switch(config-if)# ip address 1.1.1.1 255.255.255.0 ?
All features, and whether they’re enabled or disabled can be shown with show
feature
. If you run feature ?
from configure mode, there is also a
description of each feature.
switch(config)# feature ?
bash-shell Enable/Disable bash-shell
bfd Bfd
bgp Enable/Disable Border Gateway Protocol (BGP)
dhcp Enable/Disable DHCP Snooping
eigrp Enable/Disable Enhanced Interior Gateway Routing Protocol (EIGRP)
evmed Enable/Disable Generic event detectors
fcoe Enable/Disable FCoE/FC feature
fcoe-npv Enable/Disable FCoE NPV feature
flexlink Enable/Disable Flexlink
hsrp Enable/Disable Hot Standby Router Protocol (HSRP)
interface-vlan Enable/Disable interface vlan
lacp Enable/Disable LACP
lldp Enable/Disable LLDP
msdp Enable/Disable Multicast Source Discovery Protocol (MSDP)
nat Enable/Disable NAT
ntp Enable/Disable NTP
nv Enable/Disable NV Overlay
nxapi Enable/Disable nxapi
ospf Enable/Disable Open Shortest Path First Protocol (OSPF)
ospfv3 Enable/Disable Open Shortest Path First Version 3 Protocol (OSPFv3)
password Credential(s) for the user(s)/device(s)
pbr Enable/Disable Policy Based Routing(PBR)
pim Enable/Disable Protocol Independent Multicast (PIM)
port-security Enable/Disable port-security
private-vlan Enable/Disable private-vlan
privilege Enable/Disable IOS type privilege level support
ptp Enable/Disable PTP
rip Enable/Disable Routing Information Protocol (RIP)
scheduler Enable/Disable scheduler
scp-server Enable/Disable SCP server
sflow Enable/Disable sFlow agent
ssh Enable/Disable ssh
tacacs+ Enable/Disable tacacs+
telnet Enable/Disable telnet
tunnel Enable/Disable Tunnel Manager
udld Enable/Disable UDLD
vn-segment-vlan-based Enable/Disable VLAN based VN segment
vpc Enable/Disable VPC (Virtual Port Channel)
vrrp Enable/Disable Virtual Router Redundancy Protocol (VRRP)
vtp Enable/Disable Vlan Trunking Protocol (VTP)
Nexus 3545-X boot sequence
This is purely as a reference so I have a known good sequence if I ever encounter something out of the ordinary.
At this point we need to enter Y to skip Power On Auto Provisioning.