Huawei Core Switch ACL

Huawei core switches implement ACL control by defining rules to filter network traffic based on IP addresses, protocols, ports, and other criteria, which are then applied to interfaces or service modules to manage access and enhance security.Overview of ACLs on Huawei SwitchesAccess Control Lists (ACLs) on Huawei switches are sets of rules that filter packets according to conditions such as source/destination IP addresses, protocol types, and port numbers. ACLs can be applied to interfaces, traffic policies, or service modules like Telnet, FTP, or routing to control packet forwarding or discarding based on the defined rules . They help prevent unauthorized access, manage bandwidth, and protect against network attacks .Types of ACLsHuawei switches support several ACL types:Basic ACLs: Filter traffic based on source IP addresses.Advanced ACLs: Filter traffic using multiple criteria including source/destination IP, protocol type, TCP/UDP ports, fragment information, and time ranges .Numbered ACLs: Identified by a numeric range (e.g., 3000–3999 for advanced ACLs).Named ACLs: Identified by a user-defined name for easier management .Configuration StepsCreate an ACL: Use commands like acl acl-number for numbered ACLs or acl name acl-name advance for named advanced ACLs .Define ACL rules: Specify permit or deny actions for traffic based on IP addresses, protocols, or ports.Apply ACL to interfaces or service modules: ACLs only take effect after being applied to inbound or outbound directions on interfaces or within traffic policies .Optional time-based ACLs: ACLs can be configured to take effect only during specific time ranges for more granular control .Practical Use CasesRestricting access: Deny traffic from certain departments to sensitive servers while allowing authorized users .Protecting against attacks: Block specific ports (e.g., TCP 445) to prevent malware or ransomware attacks .Traffic management: Control bandwidth usage and prioritize critical services by applying ACLs in traffic policies.Verification and MaintenanceDisplay ACLs: Use commands like display acl [acl-number] to check configured rules.Modify or delete ACLs: Rules can be updated or removed as network requirements change.Troubleshooting: Ensure ACLs are applied in the correct direction and order, as rules are processed sequentially . By implementing ACLs on Huawei core switches, network administrators can effectively control traffic flow, enhance security, and ensure high service quality across the network infrastructure .