Following the upgrade of the NEO MainNet consensus nodes to 2.10.2, installation of the SimplePolicy plugin is now mandatory. Its functions are listed below:

If SimplePolicy plugin is not installed, illegal transactions will be stored in the mempool and broadcast to other nodes continuously. As the consensus nodes will not pack these transactions into blocks, the mempool will become crowded and delay normal free transactions.

Illegal transactions in this context refers to any transactions that do not follow the rules specified in the SimplePolicy settings, especially those larger than 1024 bytes with insufficient fees. Further information on the Network Fee policy can be found here.

Thus, in addition to upgrading to neo-cli-2.10.2, we urge all nodes to install the SimplePolicy plugin to ensure a healthy MainNet environment.

After installing SimplePolicy, users can verify that it is active by using the “plugins” command on neo-cli:

neo > plugins

Loaded plugins:

SimplePolicyPlugin