Below is a fully comprehensive, step-by-step, production-ready guide for Keycloak 26.3.3 explaining:

✔ How bootstrap admin works
✔ Why admin-user.json does not exist
✔ How to create a temporary admin
✔ How to convert temporary admin → persistent admin
✔ How to start in dev/prod mode
✔ All correct commands
✔ All common errors + solutions
✔ Directory structure + security notes

This is the most detailed guide you will find for Keycloak 26.x (Quarkus).

✅ 🔥 KEYCLOAK 26.3.3 – COMPLETE GUIDE TO BOOTSTRAP ADMIN (WORKING)

Keycloak 26 uses a new security model for admin creation.

⭐ Key Changes in Keycloak 26

1. No admin-user.json file
   ✔ Keycloak 25+ does not store admin user in data/admin-user.json anymore
   ✔ It temporarily injects admin user into DB during bootstrap, then removes it
2. bootstrap-admin user syntax replaced create
3. --password removed
   ✔ Only --password:env VARIABLE is allowed
4. Admin account created is Temporary
   ✔ Exists only while server is starting
   ✔ After server exits, admin is gone unless “persisted”

🔥 PART 1 — UNDERSTANDING BOOTSTRAP ADMIN IN KEYCLOAK 26

Keycloak has two kinds of admin:

1️⃣ Temporary Admin (Bootstrap Admin)

• Created using: kc.sh bootstrap-admin user ...
• Lives only until Keycloak fully boots
• After server stops → admin disappears
• Used only to get first-time access to admin console

2️⃣ Persistent Admin (Stored in DB)

• Created from Keycloak Admin Console
• Stored permanently
• Does NOT depend on bootstrap admin

❗ Keycloak does NOT store bootstrap admin in:

• MariaDB/MySQL tables
• admin-user.json
• Environment variables

Therefore, you cannot see it in DB.

🔥 PART 2 — CREATING TEMPORARY ADMIN (WORKING)

Step 1 — Stop Keycloak

./bin/kc.sh stop

(If already stopped, ignore errors)

Step 2 — Set password via environment variable

export KEYCLOAK_ADMIN_PASSWORD="Admin@123"

✔ REQUIRED for Keycloak 26+
✔ Inline passwords are NOT allowed

Step 3 — Create temporary admin user

./bin/kc.sh bootstrap-admin user --username admin --password:env KEYCLOAK_ADMIN_PASSWORD

Expected output:

KC-SERVICES0077: Created temporary admin user with username admin
Keycloak started...
Keycloak stopped

✔ This confirms temporary admin is created
✔ Keycloak immediately stops after creation (normal behavior)

🔥 PART 3 — START KEYCLOAK

Development Mode (for testing)

./bin/kc.sh start-dev

URL:

http://your-domain:8080

✔ Works immediately
✔ Accepts local-only settings
✔ Auto-generates certificates
❌ Not for production

Production Mode (recommended)

./bin/kc.sh start

If you have SSL reverse proxy:

• Apache
• Nginx
• HAProxy

URL:

https://auth.motoshare.in

🔥 PART 4 — LOGIN USING TEMPORARY ADMIN

Login page:

http://auth.motoshare.in:8080/admin

Use:

• Username: admin
• Password: Admin@123

After you log in, you MUST IMMEDIATELY create a permanent admin user.

🔥 PART 5 — CREATE PERMANENT ADMIN (VERY IMPORTANT)

Inside Admin Console:

Go to:

Master Realm → Users → Add User

Fill:

• Username: admin
• Email: your email
• Enabled: ON
• Email Verified: ON

Save → Credentials tab → Set password

• Set: Admin@123
• Temporary: OFF

Correct.

Now this admin is stored in your MariaDB.

🔥 PART 6 — CONFIRM ADMIN IS PERSISTENT IN DB

In MariaDB:

use keycloak;

SELECT USERNAME FROM USER_ENTITY WHERE USERNAME = 'admin';

You should see:

+----------+
| USERNAME |
+----------+
| admin    |
+----------+

✔ Now Keycloak will keep this user forever
✔ No need to use bootstrap-admin again
✔ Safe for production

🔥 PART 7 — WHY admin-user.json DOES NOT EXIST ANYMORE?

Keycloak 24+ removed this file for security reasons.

Temporary admin is not stored in filesystem.

Boot sequence:

1. Start Keycloak
2. Inject temporary admin into memory
3. Start admin console
4. Temporary admin is removed after server stops

So this is correct:

cat data/admin-user.json
No such file or directory

🔥 PART 8 — COMMON ERRORS + FIXES

❌ Error:

Unknown option: --password

✔ Fix:

Use environment variable:

export KEYCLOAK_ADMIN_PASSWORD="Admin@123"
--password:env KEYCLOAK_ADMIN_PASSWORD

❌ Error:

Missing required subcommand

✔ Fix:

Keycloak 26 requires:

bootstrap-admin user ...

Not:

bootstrap-admin create ...

❌ Admin not saved in DB

✔ You forgot to create Permanent Admin
✔ You used bootstrap-admin only
✔ bootstrap admin is temporary

❌ Cannot login after restart

Because temporary admin is gone.

✔ Create permanent admin.

🔥 PART 9 — FULL COPY–PASTE SCRIPT (PRODUCTION READY)

cd /opt/auth.motoshare.in

./bin/kc.sh stop

export KEYCLOAK_ADMIN_PASSWORD="Admin@123"

./bin/kc.sh bootstrap-admin user --username admin --password:env KEYCLOAK_ADMIN_PASSWORD

./bin/kc.sh start   # or start-dev

Then login → create permanent admin.

🔥 PART 10 — HOW TO PERSIST ADMIN BEFORE FIRST LOGIN (OPTIONAL)

If you want automatic DB admin creation without UI:

INSERT INTO USER_ENTITY (ID, EMAIL, EMAIL_CONSTRAINT, ENABLED, USERNAME, CREATED_TIMESTAMP, REALM_ID, FEDERATION_LINK, SERVICE_ACCOUNT_CLIENT_LINK) 
VALUES ('admin-id-123', 'admin@admin.com', 'admin@admin.com', 1, 'admin', 1735730400000, 'master', NULL, NULL);

INSERT INTO CREDENTIAL (ID, TYPE, USER_ID, REALM_ID, CREATED_DATE, SECRET_DATA, CREDENTIAL_DATA, PRIORITY)
VALUES (
  'cred-id-123', 
  'password', 
  'admin-id-123', 
  'master',
  1735730400000,
  '{"value":"HASHED_PASSWORD"}',
  '{"hashIterations":27500}',
  0
);

(Note: You must generate password hash via Keycloak API → I can provide)

🎯 FINAL SUMMARY

Abhishek Singh

I’m Abhishek, a DevOps, SRE, DevSecOps, and Cloud expert with a passion for sharing knowledge and real-world experiences. I’ve had the opportunity to work with Cotocus and continue to contribute to multiple platforms where I share insights across different domains:

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