As I was looking around in the command line interface (which is pretty new for me) I came around the esxcfg- command set. In particular the commands to manage the NIC’s (part 1) and the vSwitches (part 2) raised my interest. I decided to explore a bit further and write down how to do some standard actions. So here goes for NIC operations…
Listing all NIC’s
esxcfg-nics -l
This commands gives you a nice list of all the available NIC’s and all their properties. Those properties include name, link, speed, duplex and description.
Setting a specific link speed and duplexity of a NIC
The thing I want to do here is set my ‘vmnic3′ (the name I got from my previous command) to a speed of 100Mbps and I want to set it to full duplex. The command to do this is:
esxcfg-nics -s 100 -d full vmnic3
The ‘-s’ parameter defines the speed. This parameter can hold the values 10, 100, 1000 and 10000 respectively defining the speed to 10Mbps, 100Mbps, 1000Mbps and 10000Mbps.
The ‘-d’ parameter defines the duplexity. This parameter can hold the value ‘full’ for full duplex and ‘half’ for half duplex.
Setting link speed and duplexity of a NIC to automatic detection
To set my ‘vmnic3′ back to automatic detection I use the following command:
esxcfg-nics -a vmnic3
The ‘-a’ parameter simply sets the link speed and duplexity of the NIC back to automatic.
I hope this was useful to someone. At least I got better understanding and a little reminder for myself how to do these things. In part 2 I will cover some standard networking tasks considering virtual switches using the command esxcfg-vswitch.
Listing all virtual switches
esxcfg-vswitch -l
This commands gives you a list of all the configured virtual switches with their PortGroups and connected uplinks. Further more a lot of properties are shown about the vSwitches and PortGroups. For vSwitches it shows among other things the name, the uplinks, the number of used ports and the number of configured ports. For PortGroups it shows the PortGroup name, VLAN ID and uplinks.
Add a virtual switch called ‘TestSwitch1′
It’s really simple to add a virtual switch to an ESX server. You simply use the following command:
esxcfg-vswitch -a TestSwitch1
This creates a virtual switch with the name ‘TestSwitch1′. It still has no PortGroups and it has been set with the default amount of configured ports (64). To see all the properties use the command provided earlier to list the virtual switches. If you want to specify the number of configured ports you can use the following command:
esxcfg-vswitch -a TestSwitch1:16
This gives you a virtual switch named ‘TestSwitch1′ with 16 configured ports.
Add a PortGroup to a virtual switch called ‘TestPortGroup1′
Now we want to add a PortGroup to a virtual switch. The following command adds a PortGroup called ‘TestPortGroup1′ to our previously created virtual switch:
esxcfg-vswitch -A TestPortGroup1 TestSwitch1
This will create a PortGroup with VLAN ID 0. Notice that this time we used ‘-A’ to add the PortGroup since ‘-a’ is used for adding virtual switches. When we want to set the VLAN ID of the PortGroup we have to issue a second command. This command will set the VLAN ID of the PortGroup we just created to VLAN ID 2. The parameter ‘-p’ defines the PortGroup and ‘-v’ defines the VLAN ID you want to set it to.
esxcfg-vswitch -p TestPortGroup1 -v 2 TestSwitch1
Add an uplinkto the virtual switch and PortGroup
So now we got a virtual switch and a PortGroup. I guess we would like some connection to the outside world. So when we want to bind a physical NIC to the created PortGroup the thing to do is link the pNIC to the virtual switch and after that we automatically have the link to the PortGroup. First you need to find out what pNIC you want to bind to the virtual switch. You can check the names of the pNIC’s with the command esxcfg-nics -l. Now that we know the name we can bind it to the virtual switch. With the following command I will bind ‘vmnic4′ to the created virtual switch:
esxcfg-vswitch -L vmnic4 TestSwitch1
Notice that the l is a capital L, the normal l is already used for showing the list. Now we have configured the virtual switch correctly and we have a fully functional virtual switch with a virtual machine port group.
Remove a link from the PortGroup and virtual switch
Well first lets undo the links we just binded to the PortGroupand the virtual switch. It’s al pretty straightforward from here. If you managed to make the links it will be just as easy to undo them. The command for disconnecting the pNIC from the virtual switch is:
esxcfg-vswitch -U vmnic4 TestSwitch1
This will unlink ‘vmnic4′ from the virtual switch and the PortGroup. Notice that the ‘-U’ parameter is with a capital U just like the ‘-L’ for linking the pNIC.
Remove a PortGroup from the virtual switch
Removing the PortGroup is really simple. You just take the command you used to create the PortGroup, but instead of the ‘-A’ parameter you use the ‘-D” parameter (all capital). So the command to accomplish a deletion of the PortGroup ‘TestPortGroup1′ from virtual switch ‘TestSwitch1′ is:
esxcfg-vswitch -D TestPortGroup1 TestSwitch1
Now the virtual switch should be empty (if you didn’t do anything else to the virtual switch). There should be no PortGroups and no connected uplinks.
Removing a virtual switch
Now to set everything we have done back to the original state we have to delete the virtual switch we just made. Again this is really simple if you alter the create command. Just replace the ‘-a’ parameter with ‘-d’. The same as with the PortGroup only this time no capital characters.
esxcfg-vswitch -d TestSwitch1
And now if you list all the virtual switches again this should give you the same picture as at the beginning.
Ofcourse there are lots of things more you can do from command line networking related, but I thought this was the most basic and standard stuff you would want to do.
Scott Lowe wrote some articles about more advanced operations like
Setting Load Balancing Policies and
Modifying a PortGroup using the CLI. I hope this articles were useful for all of you. At least it has given me a nice reference for the future.
