MPLS VPN BGP AS Override

This configuration scenario demonstrates the use of BGP AS override in an MPLS VPN. In MPLS VPN network shown in the figure below, two customer sites connected to service provider MPLS network and using BGP as its PE-CE routing protocol. Implementing BGP PE-CE routing for customer imposes an issue when

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MPLS VPN OSPF Sham Link

In this example, four customer sites are connected to service provider MPLS backbone as depicted in the figure below. Two of the sites have direct low bandwidth link (384Kbps)for backup in case the primary links go down. This type of topology can result in suboptimal routing. The following sequence of

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MPLS VPN: Same OSPF Domain ID

On a Layer 3 MPLS VPN using OSPF as an IGP between PE and CE, OSPF domain ID is equivalent to the OSPF process ID by default. Therefore, OSPF routes are seen as OSPF inter-area (Type 3 OSPF LSA). By considering this behaviour, it is easy to distinguish real external

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EEM Undo Configuration Changes

Cisco Event Embedded Manager (EEM) can be used to detect and undo configuration changes on a production network like reload, removal of routing process and shutdown of management interfaces. This EEM applet is used to unshut the loopback2 when shutdown. event manager session cli username eemadmin event manager applet NO-SHUT-LOOPBACK

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EEM Unable to Establish CLI Session

I had an issue where EEM complained about couldn’t execute due to no available TTY lines. 001214: Aug 6 03:29:21.488 UTC: %HA_EM-3-FMPD_CLI_CONNECT: Unable to establish CLI session: 'Embedded Event Manager' detected the 'fatal' condition 'no tty lines available, minimum of 2 required by EEM' 001215: Aug 6 03:29:21.488 UTC: %HA_EM-3-FMPD_ERROR:

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High Memory Utilization due to hulc_flash

Two of my Cisco switches’ are having high memory utilization. They are all Cisco 2960 Catalyst switches using different IOS version. Model: WS-C2960G-24TC-L IOS: c2960-lanbasek9-mz.122-55.SE5.bin Model: WS-C2960G-24TC-L IOS: c2960-lanbasek9-mz.150-1.SE3.bin Upon investigation these switches have Dead processes holding more than 1Mb of memory which considered to be high and indicates a

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Fortigate High CPU Usage

One of my Fortigate UTMs running on FortiOS 5.2 were having high CPU usage. This issue was going on for five weeks as per my monitoring tool. This wasn’t detected until I graphed all Fortigate UTM’s CPUs in one graph. My monitoring didn’t fire an alert because the threshold was

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