Networking Knowledge Base

Core issueThis message confirms that the module booting up has synchronized the onboard ASICs that handle the transfer of packets between the backplane and the network ports. [dec] is the module number.The module reset can occur at unpredictable time...

Core issueAddress Resolution Protocol (ARP) and adjacency tables are periodically refreshed independently. This may cause tables to be out of synch until this situation ages out. Cisco Express Forwarding (CEF) is a Layer 3 (L3) IP switching technolog...

ResolutionThese are the guidelines to configure Switched Port Analyzer (SPAN) on Cisco Intelligent Gigabit Ethernet Switch Module (CIGESM):SPAN sessions can coexist with Remote SPAN (RSPAN) sessions within specified limits.  A destination port cannot...

Core IssueProtocol Independent Multicast (PIM) sparse mode is the most scalable protocol for IP multicasting. This relies on an explicit join model to forward multicast traffic. The multicast sources and receivers register with a device functioning a...

Core issueA single port on a 48-port in-line powered module does not supply power to the IP phone.ResolutionWhenever a single port has a problem with the in-line power, perform this procedure:Physically reseat the module and re-insert it firmly.   Pl...

Core issueThe Cisco processors have timers that guard against certain types of system hangs. The CPU periodically resets a watchdog timer. The watchdog timer basically controls the time of each process. If the timer is not reset, a trap occurs. If a ...

Core issueA watchdog timer is a hardware countdown timer that the software periodically resets. If the software gets stuck for two to six seconds, the timer interrupts the CPU, and Catalyst OS (CatOS) crashes. This problem usually occurs due to a cod...

Core issueThis error means that the module in the indicated slot was powered off for the reason stated in the error message.For example, this error message indicates that the source is a switch processor (SP) and the condition occurred in the SP on t...

Core issueWhen multiple ports are configured to have duplex mismatch with the peer, and under heavy broadcast or multicast traffic, the VLANs disappear after a period of time.This problem is not seen if the duplex mismatch condition is corrected afte...

Core issueIf the %L3_ASIC-DFC3-4-ERR_INTRPT: Interrupt TF_INT:FI_DATA_INT error message occurs along with the %MLSCEF-DFC3-7-SHADOW_SSRAM_INCONSISTENCY error message,  then it indicates that system has detected corrupted SSRAM entries and the softwar...

Core IssueThis document responds to frequently asked question concerning IP address determination, such as these: How can I determine the IP address and mask on the router? How can I determine the IP address of the TFTP server for Windows 95?How can ...

Core issueThe %MCAST-4-RX_LVRANGE: IGMP: Rcvd Leave in the range of 01-00-5e-00-00-xx Or %MCAST-5-RX_IGMPLV:IGMP: Rcvd IGMP Leave  01-00-5e-00-00-xx error message indicates that the switch received an Internet Group Management Protocol (IGMP) leave f...

ResolutionIf you are using the Microsoft Windows NT operating system with the original HyperTerminal version, and you need to issue a break sequence to get to the ROM monitor (ROMmon) mode on a Cisco router, perform one of the following options:Upgra...

ResolutionCatalyst 2950, 2955, 2970, 3750 and 3750 Metro Series Switches support Access Control Lists (ACLs) for network traffic filtering and security purposes. In Catalyst 2950 and 2955, ACLs can be created using the Command Line Interface (CLI) or...

ResolutionThe fiber interface has a fixed speed and does not support duplex options, but you can set the interface to negotiate link parameters (the default) or not to negotiate.For fiber Gigabit Ethernet fiber interfaces, the default is no speed non...