The Debug Ip [Protocol] Cisco command

The 'debug ip [protocol]' command is a powerful tool that allows network engineers and technicians to troubleshoot and analyze various aspects of IP traffic on Cisco networking devices. It enables the capture and display of detailed information related to specific IP protocols, helping identify and resolve network connectivity issues or performance problems.

Command Syntax:

The general syntax of the 'debug ip [protocol]' command is as follows:

debug ip [protocol] [keyword] [level]


  1. [protocol]: This argument specifies the IP protocol for which debugging information is required. Common protocols include:

    • ip - General IP-related information
    • ip accounting - Accounting information related to IP traffic
    • ip arp - Address Resolution Protocol (ARP) information
    • ip bgp - Border Gateway Protocol (BGP) information
    • ip cef - Cisco Express Forwarding (CEF) information
    • ip dhcp - Dynamic Host Configuration Protocol (DHCP) information
    • ip eigrp - Enhanced Interior Gateway Routing Protocol (EIGRP) information
    • ip forward - IP forwarding information
    • ip http - HTTP traffic information
    • ip icmp - Internet Control Message Protocol (ICMP) information
    • ip igmp - Internet Group Management Protocol (IGMP) information
    • ip nat - Network Address Translation (NAT) information
    • ip ospf - Open Shortest Path First (OSPF) information
    • ip pim - Protocol Independent Multicast (PIM) information
    • ip policy - IP policy information
    • ip rip - Routing Information Protocol (RIP) information
    • ip route - IP routing information
    • ip rsvp - Resource Reservation Protocol (RSVP) information
    • ip ssh - SSH traffic information
    • ip tcp - Transmission Control Protocol (TCP) information
    • ip telnet - Telnet traffic information
    • ip tftp - Trivial File Transfer Protocol (TFTP) information
    • ip vrf - Virtual Routing and Forwarding (VRF) information
  2. [keyword]: This argument specifies the specific aspect of the protocol for which debugging information is required. The available keywords vary depending on the protocol.

  3. [level]: This argument specifies the level of detail in the debugging information. The options typically include:

    • 1 - Summarized information
    • 2 - Detailed information
    • 3 - Very detailed information


When executed, the 'debug ip [protocol]' command activates debugging for the specified IP protocol and displays the debugging information in real time. The output typically includes:

Equipment Compatibility:

The 'debug ip [protocol]' command is supported on a wide range of Cisco networking devices, including routers, switches, firewalls, and access points. The specific protocols supported may vary depending on the device model and operating system version.

Troubleshooting and Diagnostics:

The 'debug ip [protocol]' command is commonly used to troubleshoot various network issues, including:

By analyzing the debugging information, network engineers can identify the root cause of the problem and implement appropriate solutions.


It's important to use the 'debug ip [protocol]' command judiciously. Enabling debugging can impact the performance of the device and can generate a large volume of output, making it challenging to analyze. Therefore, it's recommended to disable debugging when it is no longer necessary.

debug ip [protocol] Usage Examples

The syntax for debug ip [protocol] command in Cisco is:

debug ip [protocol] [level]

The following are examples of the debug ip [protocol] command:

debug ip events
debug ip routing
debug ip forwarding
debug ip fragmentation
debug ip multicast
debug ip unicast
debug ip input
debug ip output
debug ip routing table updates
debug ip checksum
debug ip ttl expire
debug ip fragmentation errors
debug ip [protocol]

For example, to enable debugging of ICMP events, use the following command:

debug ip icmp