graph LR
Fail2ban_Daemon_Server_["Fail2ban Daemon (Server)"]
Jail_Action_Engine["Jail & Action Engine"]
Database_Manager["Database Manager"]
Client_Server_Communication["Client-Server Communication"]
Configuration_Manager["Configuration Manager"]
Background_Tasks_Observer_["Background Tasks (Observer)"]
Fail2ban_Daemon_Server_ -- "Manages" --> Jail_Action_Engine
Fail2ban_Daemon_Server_ -- "Manages" --> Database_Manager
Fail2ban_Daemon_Server_ -- "Manages" --> Client_Server_Communication
Fail2ban_Daemon_Server_ -- "Manages" --> Background_Tasks_Observer_
Fail2ban_Daemon_Server_ -- "Receives configuration from" --> Configuration_Manager
Jail_Action_Engine -- "Managed by" --> Fail2ban_Daemon_Server_
Jail_Action_Engine -- "Accesses" --> Database_Manager
Jail_Action_Engine -- "Interacts with" --> Background_Tasks_Observer_
Database_Manager -- "Managed by" --> Fail2ban_Daemon_Server_
Database_Manager -- "Accessed by" --> Jail_Action_Engine
Database_Manager -- "Accessed by" --> Background_Tasks_Observer_
Client_Server_Communication -- "Managed by" --> Fail2ban_Daemon_Server_
Client_Server_Communication -- "Sends commands to" --> Fail2ban_Daemon_Server_
Configuration_Manager -- "Provides configuration to" --> Fail2ban_Daemon_Server_
Configuration_Manager -- "Provides configuration to (indirectly via Daemon)" --> Jail_Action_Engine
Background_Tasks_Observer_ -- "Managed by" --> Fail2ban_Daemon_Server_
Background_Tasks_Observer_ -- "Accesses" --> Database_Manager
Background_Tasks_Observer_ -- "Interacts with" --> Jail_Action_Engine
click Fail2ban_Daemon_Server_ href "https://github.com/CodeBoarding/GeneratedOnBoardings/blob/main//fail2ban/Fail2ban_Daemon_Server_.md" "Details"
click Jail_Action_Engine href "https://github.com/CodeBoarding/GeneratedOnBoardings/blob/main//fail2ban/Jail_Action_Engine.md" "Details"
click Database_Manager href "https://github.com/CodeBoarding/GeneratedOnBoardings/blob/main//fail2ban/Database_Manager.md" "Details"
click Client_Server_Communication href "https://github.com/CodeBoarding/GeneratedOnBoardings/blob/main//fail2ban/Client_Server_Communication.md" "Details"
click Configuration_Manager href "https://github.com/CodeBoarding/GeneratedOnBoardings/blob/main//fail2ban/Configuration_Manager.md" "Details"
click Background_Tasks_Observer_ href "https://github.com/CodeBoarding/GeneratedOnBoardings/blob/main//fail2ban/Background_Tasks_Observer_.md" "Details"
The fail2ban architecture is primarily a client-server model, with a central daemon managing security policies based on log file analysis. The core functionality revolves around detecting malicious patterns in logs and executing predefined actions (like banning IP addresses).
The central orchestrator of the Fail2ban system. It manages the lifecycle of jails, handles client commands, and coordinates with other core components like the database and background observer. It is the main control hub.
Related Classes/Methods:
Encapsulates the core logic for monitoring log files, detecting malicious patterns, managing failed attempts, and executing ban/unban actions. Each "jail" instance represents a specific service being protected, applying filters and actions.
Related Classes/Methods:
fail2ban.server.jail.Jail(38:352)fail2ban.server.filter.Filter(56:998)fail2ban.server.failregex.FailRegex(413:465)fail2ban.server.datedetector.DateDetector(221:549)fail2ban.server.failmanager.FailManager(37:164)fail2ban.server.action.CommandAction(287:1041)fail2ban.server.actions.Actions(49:744)
Provides persistent storage for Fail2ban's operational data, including banned IP addresses, their ban times, and log file positions. It handles all database interactions (creation, updates, queries).
Related Classes/Methods:
Facilitates asynchronous communication between Fail2ban clients and the central daemon. It handles incoming client connections, parses commands, and dispatches them to the appropriate server-side handlers.
Related Classes/Methods:
fail2ban.server.asyncserver.AsyncServer(197:340)fail2ban.server.transmitter.Transmitter(36:522)fail2ban.client.fail2banclient.Fail2banClient(53:461)
Responsible for reading, parsing, and applying Fail2ban's configuration files. It handles the hierarchical structure of configuration, including includes and variable interpolation, to set up jails, filters, and actions.
Related Classes/Methods:
fail2ban.client.configurator.Configurator(34:90)fail2ban.client.configreader.ConfigReader(61:179)fail2ban.client.jailreader.JailReader(44:312)fail2ban.client.actionreader.ActionReader(36:103)fail2ban.client.filterreader.FilterReader(36:98)
A dedicated thread for handling periodic and asynchronous operations, primarily monitoring for the expiry of bans and triggering unban actions. It also performs database maintenance tasks.
Related Classes/Methods: