Networking Knowledge Base

Core IssueThe SVIP error interrupt handler is called because of a Packet Memory Application-Specific Integrated Circuit (ASIC) (PMA) error. This usually occurs when an ASIC on the Versatile Interface Processor (VIP) detects a parity error, as shown i...

ResolutionIf packet loss occurs while connecting a switch to a server, perform these steps:    Verify that the cable is good by using a cable tester or replace it with a known good cable.Verify that the Network Interface Card (NIC) is compatible and ...

ResolutionThese are the three ways to monitor voice traffic on Cisco Catalyst switches:Through Switched Port Analyzer (SPAN) and Remote Switched Port Analyzer (RSPAN):With SPAN, packets are copied to a destination port for analysis. Cisco Catalyst sw...

ResolutionOutput scheduling is used to ensure that important traffic does not get dropped in the event of heavy over-subscription. Quality of Service (QOS) has different stages of operation and implementation. Output scheduling is applied on the inte...

Core IssueConsole overrun errors occur when the router cannot process console inputs properly.ResolutionThis issue is usually caused by a problem with the terminal emulation software. Try Hyperterminal if you currently use a different emulation progr...

Core issueIf the standby supervisor engine module is not coming online (indicated by the status of other or faulty in the output of the show module command, or indicated by amber status LED), it may be due to one of the common reasons indicated in th...

Core issueThe DTP-5-DOMAINMISMATCH: Unable to perform trunk negotiation on port [chars] because of VTP domain mismatch error message indicates that the two ports in the trunk negotiation belong to different VTP domains. Trunking can be configured onl...

Core issueA software upgrade on the active Supervisor fails even after you copy the code from  the bootflash on the secondary (up and running new code) directly to the bootflash on the  primary. Cisco IOS  on both Supervisor Engines must be the same ...

Core issueMAC address reduction is disabled, not permitting extended-range VLANs to be created.ResolutionExtended (VLAN numbers up to 4096) was first supported on the Catalyst 6000 series in CatOS 6.1(1), and on the Catalyst 4000 series in CatOS 7.2(...

Core issueIn Catalyst OS (CatOS), a default gateway must be defined on the Supervisor Engine.  This default gateway is usually the IP address of an active interface on the router.  The router may be internal, such as the MultiLayer Switch Feature Car...

Core IssueIn order for Border Gateway Protocol (BGP) to advertise a classless network generated by issuing the network BGP configuration command, a valid route must exist in the routing table.ResolutionA valid route is an exact route matching the net...

Core IssueBecause the Cisco 3600 series routers have two Flash SIMM slots and there is no requirement that the Flash SIMMs be the same size, it is possible to add a second Flash SIMM on a router with only one SIMM installed and copy an image to it us...

Core IssueNetwork Address Translation (NAT) with support for the Microsoft NetMeeting application requires either a J or an O image, enterprise feature set, or Cisco IOS  Software Firewall feature set respectively.ResolutionYou need to be running a C...

Core IssueIn this case, the file system on the device from which the CPU tries to load the Cisco IOS  Software image is corrupted.ResolutionDepending on the router model, choose from these resolution options:Boot from another Flash device.Boot from t...

Core IssueThe TLB (Load/Fetch) Exception error message is often the result of a bus error. This is an example of the error message: *** System received a Bus Error exception ***Access address = 0x3c210040signal= 0xa, code= 0x1c, context= 0x60e632f0PC...