Step 2 Select the file manager menu and create a file called ops.txt
Step 3 To set a user as admin, simply add their username to a new line, save the file, and restart your server.
Step 3 Restart your server
This will grant immediate admin access to the players you add, including access to all plugins.
Method 2 Add a Minecraft server Admin Using /op username
This can be done in two ways
Step 1 Login to the dedicatedminecraft control panel. Step 2 Select the Minecraft server that you want to add admin on and you'll be met with a console window. Step 3 You'll see the type command on the console and type This op username and enter. change the username to the username you'd like to make admin.
This command will grant immediate admin access to the players you add, including access to all plugins (unless otherwise configured), you will not need to restart server.
Customize admin permissions
Will require you to install permissions plugin to designate different access levels for your admins.GroupManager or PermissionsEX
useful Minecraft Server admin commands
ban <playername> [reason]
Blacklists the name playername from the server so that they can no longer connect. Note: Bans supersede any whitelisting in place.
ban-ip <ip-address \| playername>
Blacklists an IP address so that all subsequent connections from it are rejected.
ip-address must be valid orplayername must be online.
Displays the banlist. To display banned IP addresses, use the command "banlist ips"
Revokes a player's operator status.
kick <playername> [reason]
Forcibly disconnects playername from the server, displaying an optionalreason to them.
Playername must be online.
Shows the names of all currently-connected players (the same can be achieved when pressing tab)
Always succeeds, even in a command block.
Grants playername operator status on the server.
Removes playername from the blacklist, allowing them to connect again.
Removes ip-address from the IP blacklist, allowing players from that IP address to connect to the server.
ip-address must be valid.
Forces the server to write all pending changes to the world to disk.
Disables the server writing to the world files. All changes will temporarily be queued.
Enables the server writing to the world files. This is the default behavior.
Gracefully shuts down the server.
whitelist <add \| remove> <playername>
Adds or removes playername from the whitelist.
Displays all players in the whitelist.
whitelist <on \| off>
Enables/disables the server's use of a whitelist. Note: Server ops will always be able to connect when the whitelist is active, even if their names do not appear in the whitelist.
Reloads the list of playernames in white-list.txt from disk (used when white-list.txt has been modified outside of Minecraft).