Telnet Connection Timed Out

Issue: Telnet connection timed out when accessing the CPE via the secondary management interface loop1 as shown in the figure. The disconnection happens when the user stop sending data across the telnet session (e.g. stop typing commands). Findings: Started my investigation by taking a packet capture on the Fortinet Fortigate

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BGP Cost Community

This post explores the use of BGP cost community to prefer one path over the other in a multipath environment as shown in the figure. BGP cost community is a nontransitive extended community attribute that is passed to iBGP peers only. This feature allows us to customize the BGP best

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Apple Devices Cannot Connect to Meraki AP

Issue: Apple devices like iPads and Macbook Pro cannot connect to Meraki AP. Sometimes devices can connect but get disconnect later on. Platform: All Cisco Meraki AP platform. Software version is unknown this is due to the fact Cisco Meraki doesn’t disclose it. Solution: Cisco Meraki APs that are configured

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MPLS VPN Hub and Spoke

Sometimes customer wants to implement MPLS VPN hub and spoke topology which allows the customer to control traffic between spokes and also to other resources like the Internet (access restriction). Therefore, the hub acts as a central transit point between spoke sites. The MPLS VPN hub and spoke topology requires

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Inter-AS MPLS VPN: Back to Back VRF

Back to back VRF is one of the options to connect customer sites that are geographically dispersed and also connected to different service provider MPLS VPN backbones. This option is the simplest approach for allowing MPLS VPN providers to exchange VPN routing information for CE sites. The border provider edge

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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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