SNMP

SNMP, or Simple Network Management Protocol, is a protocol used for managing and monitoring network devices. It allows network administrators to collect information about network performance, detect network faults, and configure network devices. SNMP operates over UDP port 161.

What is SNMP

SNMP, or Simple Network Management Protocol, is a widely used protocol for network management. It enables network administrators to manage network performance, find and solve network problems, and plan for network growth. SNMP works by sending messages, called protocol data units (PDUs), to different parts of a network.

SNMP is used to monitor network-attached devices for conditions that warrant administrative attention. It is commonly used in network management systems to monitor network-attached devices for conditions that warrant administrative attention. Devices that typically support SNMP include routers, switches, servers, workstations, printers, modem racks, and more.

SNMP was first introduced in 1988 and has since become a standard protocol for network management. It operates mainly over UDP port 161, and it uses a simple set of operations to query and modify the information stored in the device's management information base (MIB). The protocol has evolved over time, with SNMPv3 being the latest version, which includes enhanced security features.

SNMP runs on TCP and UDP port 161 and is official IANA port.

Security risk

If SNMP port 161 is open and the service is running, it can be a significant security risk. Unauthorized access to SNMP can allow attackers to gather sensitive information about the network, such as device configurations and network topology. Additionally, if SNMP is not properly secured, it can be used to modify network device settings, potentially leading to network disruptions or breaches.

In our UFW tutorial you can follow instructions how you can configure UFW to close port 161. Use StackChanges to monitor if the SNMP port is closed and stays closed. StackChanges will send an alert if port 161 is open again.