Convert VLAN ID for Tagged HPE/Aruba VSA

To return tagged VLANs to an Aruba switch, the HPE vendor specific attribute HPE-Egress-VLAN-ID or HPE-Egress-VLAN-Name is needed.
If the VLAN names are not equal on every switch, the VLAN ID presents a good alternative. There are, however, a few steps we need to do before we can return the VLAN ID to the switch.

Step by Step

  1. Identify your needed VLAN ID
  2. Convert it into a hexadecimal number with three digits
  3. Add 31000
  4. Convert the combined number back into decimal
  5. Use the number as the return value in your RADIUS server

That is how we manual way. But you can just add your VLAN ID to 822083584.‬

Example

I will write up an example for all the described steps:

  1. Identify:
    VLAN ID: 71
  2. Convert:
    71 = 0x047
  3. Add 31000:
    0x31000047
  4. Convert:
    822083655
  5. Use as RADIUS VSA:
    See my page about returning tagged VLAN in ClearPass (soon)

Quick way:
822083584 + 71 = 822083655

Tool

I have released a small Python script that converts VLAN IDs to the needed value. You can download it as a command-line executable here or try it here:

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