Quick Overview of Proxmox VE REST API

Creating An API User

Log into the Proxmox VE web UI
Select Datacenter from the left navigation menu
Select Users from the left sub-navigation menu
Click the Add button at the top of the main content area
Enter the Username API, set the Realm to Proxmox VE authentication server and set and confirm a password > Click Add
Select API Tokens from the left sub-navigation menu
Select API@pve for the username
Enter a secret key into the Token ID field > Click Add
TIP: Use a random string generator to create a unique Token ID String Generator
Copy the displayed Token ID and Secret to a text document for use later
Close the dialog
Select Roles from the left sub-navigation menu
Click the Create button at the top of the main content area
Name the new role APIAdmin and select all available Privileges > Click Create
NOTE: These permissions can be fine-tuned later
INFO: More information on each privilege can be found here
Select Permissions from the left sub-navigation menu
Select the Add > User permission at the top of the main content area
Set the Path to /, select the API@pve user and set the Role to APIAdmin > Click Add

Downloading Postman

Postman is an API platform for building and using APIs. Postman simplifies each step of the API lifecycle and streamlines collaboration so you can create better APIs—faster. - https://postman.com

Download Postman Download
Extract or install Postman
Launch Postman
Click the Skip and go to app link at the bottom left of the splash screen
Select File > Settings from the top menu bar
Disable SSL Certificate Verification and Send anonymous usage data to Postman > Close the Settings dialog window

Proxmox API Authentication

In Postman, click the + next to the Overview tab to create a new HTTP request tab
Complete the HTTP Request form as follows:
- Method: POST
- URL: https://DNSorIP:8006/api2/json/access/ticket
- Body: x-www-form-urlencoded
  - username: API@pve
  - password: <API@pve Password>
Click the Send button
From the response, copy the ticket value and CSRFPreventionToken values to a text document for use later

Proxmox Version API Call

In Postman, click the + next to the Overview tab to create a new HTTP request tab
Click the Cookies link below the send button
Type the API URL up to /json/, (ie https://DNSorIP:8006/api2/json/) > Click Add
Click Add Cookie
Replace the Cookie_1 key with PVEAuthCookie
Replace the value with the ticket value from authentication response, the result should look like
PVEAuthCookie=PVE:API@pve:611F9752::aXrYKYqiv8oV/MetlZl6FC40HSULSj4gt9EjDsTIwq+GXVXpkGyqvMlXqmGP6LP/rUYUgIKkSh9ioEhz91kR9/i+jDobDFIAtjBGLIP4yJVbxbtU6hfJL91YQNyYgvHqkPv4/W6EYWir5+LFQc3womgqVE9gKApk61J8zxFNTTjwh87HbMAtv12fvAqiICEqRMdqvE6ySJF5a8E+rOlqa46MlTbUTnzCbqPTY6tWBYHryy8WS8Typ3aSkOKecup18sCBtzqxnkm9bpws+f8vW9FdJV8eKnR+MbFLQtv/re5Cw/J7RpdvcQvMsZ0JLFWqnTaPgRzBc/mM7xZBKeCiSA==
Click Save > Close the Manage Cookies dialog window
Complete the HTTP Request form as follows:
- Method: GET
- URL: https://DNSorIP:8006/api2/json/version
- Headers:
  - CSRFPreventionToken: <CSRFPreventionToken value from authentication response>
Click the Send button
The response body should show details about the current Proxmox version

Proxmox Nodes API Call

In Postman, right click the /version HTTP request tab > Duplicate Tab
Change the URL to https://DNSorIP:8006/api2/json/nodes
Click the Send button
The response body should show details about the available Proxmox node(s)

Proxmox Node Status API Call

In Postman, right click the /version HTTP request tab > Duplicate Tab
Change the URL to https://DNSorIP:8006/api2/json/nodes/<node name>/status
Click the Send button
The response body should show details about the selected Proxmox node

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