24 - 07 - 2024

Omniswitch 6900 VLAN translaction

This is update to my previous article: VLAN translaction on Alcatel but configuration created for OmniSwitch 6900.

VLAN 4050 - The VLAN that exists on the translating switch, to prevent VLAN overlapping it will be translated to VLAN900.

LINKAGG 100 - The uplink to other switch that has VLAN4050 configured but for other dedicated service. Due VLANs overlapping translaction is required.

PORT 1/9 & PORT 1/7 - Trunks ports to a server or other VLAN aware device (switch/router). Frames are represented as tagged frames with VLAN 900.

HP 6125XLG Line (SSH/AUX etc.) authentication

I have found tricky to configure SSH on HP switches integrated in HP BladeSystem C7000 chassis.

The manuals doesnt cover are requiremnts steps so here you will find the way how to configure the SSH/CONSOLE/AUX lines.

Read more: HP 6125XLG Line (SSH/AUX etc.) authentication

Configuring netbsd (sparc) appliance for IOU

There are alot of articles covering subject of IOU running on Linux and Unix. I would like to go deeper and specific how we can create some useful confiugration on NETBSD/SPARC to have this maybe easier in some cases.

The goals I've set are:

  • Ony one IOU instance per NETBSD appliance
  • Use GNS3 clouds (UDP TAP) to provide connectivity between each NETBSD instance and other part of networks. This was really forced, in first instance I tried to create some kind of bridge, but NETBSD didn't recognize second LE (ethernet card) correctly
  • Make it as more automaticated as it is possible
  • Keeps each service separated

Read more: Configuring netbsd (sparc) appliance for IOU

L3VPN on Cisco XR - without MPLS enabled switches

You can be put in situation to connect two or more L3 devices using L3VPN. The configuration isn't complex, and will work unless the path between devices invloves the non-MPLS enabled switches. If you connect ASR routers using other devices in the network it can be tricky. BGP sessions is not an issue, but MPLS tags. For L3VPN two labels are required:

  • Outer Label - specifices outgoing interface to reach L3VPN enabled neighbor.
  • Inner Label - provides information about VRF instance for the neighbor

The issue I got was lack of Outer Label because the path toward L3VPN neighor was not MPLS-enabled. It was simply 802.1Q subinterface, on top of bundle-interface. The sessions have been established, but no traffic was seen on opposite site.

Read more: L3VPN on Cisco XR - without MPLS enabled switches

Linux routing with BIRD and multiple tables

Sometime is useful to rely on dynamic routing protocols like OSPF or BGP. For example we could use OSPF for two customers networks that should be never mixed in the same routing table. 


Read more: Linux routing with BIRD and multiple tables

Alternative for SVI in Cisco routers - BDI

I had to have some alternative for SVIs used on MLS, but configured on router (CSR1000v). The solution required to have two phsycial interfaces bridge with IP address on top of it. In linux the solution its so trivial, not even worth to talk about doing it via either openvswitch or bridge utils.

Read more: Alternative for SVI in Cisco routers - BDI

VLAN translaction on Alcatel

In this article I would like to descirbe  the Alcatel VLAN Translation service by using ethernet-services feature. The service allows to translate VLAN 802.1 taggs as for this example from 1000 to 100, in the way similar to the NAT. It could be use to provide the L2 connectivity for networks that have diffrent VLAN numbering. 

Read more: VLAN translaction on Alcatel


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