BGP Route Reflector Design Options (Part 2): Hierarchical 2-tier Route Reflectors, MCIDs
The issue of the previous Route Reflector (RR) design is that it is not protected from a single point of failure: if a RR goes…
Read more →BGP Route Reflector Design Options (Part 1): Inter-Cluster Peerings
If we have many iBGP routers within an AS, to solve the scalability issue of the full-mesh requirement we can deploy one (or more) iBGP…
Read more →Configuring Multicast routing (Part 4): PIM Assert, Designated Router, Null Register
We extend our previous topology with a few new routers to demostrate how the PIM Assert mechanism work. This time we configure PIM with dense-mode…
Read more →Configuring Multicast routing with PIM Sparse-Mode (Part 3): Bootstrap Router (BSR)
In the previous multicast post we configured the RP statically. If we have a lot of routers this solution is not going to be scalable…
Read more →Configuring Multicast routing with PIM Sparse-Mode (Part 2): RPF checks, static mroute
We continue the previous multicast lab. This time we take a look at how RPF check works, how we can prevent RPF failures, and how…
Read more →Mirroring traffic with SPAN, RSPAN and ERSPAN
These features allow us copy the traffic of a switchport or an entire VLAN and send the copied frames to another switchport. This destination port…
Read more →Implementing VPLS part 2: BGP Autodiscovery
In the previous post about VPLS implementation we configured the remote PEs manually under the VFI, like this: This solution is not scalable if the…
Read more →Implementing MPLS L2VPN services on SR OS part 1: Epipe
We're going to configure Layer 2 services for customers over an MPLS cloud using SR OS routers. First we're going to take a look at…
Read more →Troubleshooting OSPF adjacencies
I've been experimenting with different router images and I tried to establish the OSPF neighbor adjacency between a Cisco and an Alcatel (SR OS) router.
Read more →Configuring Multicast routing with PIM Sparse-Mode (Part 1)
In this post I'm going to walk through how we can configure basic multicast routing using PIM Sparse-Mode. I'm going to walk though how the…
Read more →Protecting Stateless/Stateful DHCPv6 server with DHCPv6 Guard
In this lab I'm going to use the same simple topology which I used in this post. Except that we're going to take a look…
Read more →Configuring QoS Policer at the Provider Edge router
I'm going to configure a policer to restrict and meter the traffic coming from Customer 1 on one of the PE router. The topology I'm…
Read more →Configuring IPv6 First-Hop Security (RA Guard, IPv6 Snooping)
In this lab we're going to implement IPv6 FHS with Router Advertisement Guard and IPv6 Snooping and in the following post I'll show how to…
Read more →Implementing STP Root Guard and Loop Guard
These two are optional features we can configure with Spanning-Tree. They are mutually exclusive: we configure one or the other, but you cannot configure both…
Read more →Configuring E-LAN (VPLS) service over the MPLS cloud using CSR1000v routers
I'm going to build a L2VPN service for Customer 1 sites (purple), and create an "emulated" switching environment within the MPLS core: CE1, CE3, and…
Read more →How to secure Apache2 webserver with SSL
Nowadays every major website operates over HTTPS, aka have that little padlock next to the URL in our browsers. It means that we can establish…
Read more →How to set up an NFS server and share files on Linux
With the help of NFS we can share a filesystem via the network. On the client side we can mount the NFS filesystem just like…
Read more →LVM – Logical Volume Management in Linux
With the implementation of LVM we can reallocate storage space and extend our storage volumes really easily. In the example below I’d like to show…
Read more →iptables – NAT MASQUERADING in Linux
In a previous post I wrote about how can we accomplish NAT with Cisco devices. This time let’s examine how can we implement the same…
Read more →Configuring MPLS L3VPNs – Part 2
After finishing the MPLS configuration in this post, I thought to take a closer look at the MPLS network, especially the labels: with the help…
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