Create etherstub + VNIC & add it to zone - Smartos

This howto will show you how to create a etherstub and add a vnic on top of it. See a etherstub as a virtswitch which is indipendent from the phsycal NICs.

1. Create a ETHERSTUB 
NB: ETHSTUBNAME must end with a number; for instance a valid name would be happyether69
# nictagadm add -l ETHSTUBNAME


2. Now lets create a dummy VNIC on the ETHERSTUB
# dladm create-vnic -l ETHSTUBNAME VNICNAME -m MACADDR


- The end result should be the following:
>>>
[root@homelab ~]# dladm show-vnic
LINK         OVER       SPEED MACADDRESS        MACADDRTYPE VID  ZONE
net0         bnx2       0     72:bw:20:79:9a:aa fixed       0    4da9efe9-4904-cacd-d4ac-c3a34b119472
ovpn1        int_ovpn1  0     8:0:27:c1:50:1a   fixed       0    --
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3. Add the newly create VNIC to an existant zone
1a. Create a file somewhere in /opt/ and call it something like "add_dummy_vnic.json"
2a. Add the following in it:
>>>
  {
    "add_nics": [
        {   
      "interface": "VNICNAME", 
      "nic_tag": "ETHSTUBNAME",
      "mac": "c9:aa:q5:8d:1c:qf",
      "model": "e1000",
      "mtu": "9000"
   }
    ]
}
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3a. Assuming the zone is already powered off, proceed adding the new VNIC
# cat /opt/vmadm_templates/add_dummy_vnic.json | vmadm update UUIDNAME-925c-e35e-e5a2-874630dee577
4. If all went well a similar output should be expected:
>>>
# vmadm get UUIDNAME-925c-e35e-e5a2-874630dee577 |json nics

[
  {
    "interface": "eth0",
    "mac": "12:a8:0f:lb:01:bb",
    "nic_tag": "admin",
    "gateway": "172.12.0.1",
    "gateways": [
      "172.12.0.1"
    ],
    "netmask": "255.255.255.0",
    "ip": "172.12.0.210",
    "ips": [
      "172.12.0.210/24"
    ],
    "primary": true
  },
  {
    "interface": "eth1",
    "mac": "c9:aa:q5:8d:1c:qf",
    "nic_tag": "ETHSTUBNAME",
    "allow_ip_spoofing": true,
    "mtu": 9000
  }
]
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For more info see 
https://smartos.org/man/1m/dladm
https://smartos.org/man/1m/vmadm

Job done.