Cisco: 2-Bytes / 4-Bytes ASN BGP scenarios
In my last post I wrote some basics about the new 4-bytes AS number which is supported on new Cisco IOS images. Now I would like to give you a brief overview about different BGP peering scenarios that you can meet in the real world. Even if the configuration examples in this article are on a Cisco hardware with the latest IOS, the BGP scenarios can be applied to [...] Continue Reading…
Popularity: 23% [?]
Cisco: The basics about VRF implementation
VRF, meaning Virtual Routing and Forwarding, is a technology implemented in the IP network routers that allows multiple instances of a routing table to exist on the same router in the same time. Since each VRF is independent, the same IP subnet can exist in 2 different VRFs. Basically you can overlap one IP address in 2 VRFs but without conflicting with each other. Even this is possible, I [...] Continue Reading…
Popularity: 100% [?]
Wireshark’s most useful display filters
Now and then, especially when you expect less, the network crashes or encounter an issue and then you had to troubleshoot. Sometime the problem is right there, you can see it and it’s easy to fix, but in other cases you’ll have to put an eye in the packets that are traveling through it and search deeper for the solution. When it comes to network sniffing or packet capturing [...] Continue Reading…
Popularity: 36% [?]
How to integrate GNS3 with Virtual PC
In this article I want to show you how to extend your posibilities to test a network in GNS3. Sure, it’s simple sometime to use a Loobpack interface on one of your edge routers to simulate an external network, but sometime is useful to have something connected to the router port. Take as an example QoS marking and classification. If you want to mark something inbound, then you need [...] Continue Reading…
Popularity: 42% [?]
Cisco: How to configure simple IP SLA monitor
Before we begin let’s see what is this SLA term, for those of us who are not very familiar with the Service Provider terms. IP Service Level Agreements (SLAs) enable customers to assure new business-critical IP applications, as well as IP services that utilize data, voice, and video, in an IP network. With Cisco IOS IP SLAs, users can verify service guarantees, increase network reliability by validating network performance, [...] Continue Reading…
Popularity: 29% [?]
