IPv6 is not really new. According to Google, 10% of all users that access Google, do this over an IPv6 connection (Source). My blog is also accessible over IPv6 since its start in January 2014 (and since January 2016 only over HTTPS - thanks to Let’s Encrypt!).
When I talk with customers about IPv6, I often hear things like “Oh, we had to disable it. Too much problems!” or “We had to disable it.
Disclaimer: Thanks to ALE Deutschland GmbH, the german subsidiary of Alcatel-Lucent Enterprise, for loaning me two OmniSwitch 6450 switches.
Who’s Alcatel-Lucent Enterprise? I’m quite sure that you know Alcatel-Lucent, a leading vendor for telecommunication and networking equipment. But do you know Alcatel-Lucent Enterprise (ALE)? In April 2015, Nokia placed an offer to buy Alcatel-Lucent for ~ 15 billion euro. Six months before, in October 2014, Alcatel-Lucent sold his enterprise business to China Huaxin.
In January 2014 I wrote a blog post about network flooding because of Windows NLB clusters in unicast mode. Yesterday, Windows NLB, HP switches and I met again.
After moving a customers core network from HP 5400zl switches to two IRF stacks with HP 7506 switches, multiple Windows NLB clusters stopped working. Because the Windows NLB used multicast operation mode, it was instantly clear that the switches were the problem.
Last week, my colleague Claudia and I have ported a HP ProVision configuration to HP Comware. Unexpectedly, it wasn’t routing or VLANs or OSPF that caused headaches, it was a Wake-on-LAN (WoL). Depending on the used tool, the magic packet (which wakes up the computer) is a broadcast (255.255.255.255) or a subnet-directed broadcast (e.g. 192.168.200.255). So it was important to know what tool the customer used.
This is how HP ProVision implements subnet-directed broadcasts:
Building networks in the cloud is sometimes hard to understand. A common mistake is to believe that all VMs can talk to another, regardless of the owner, and that all VMs are available over the internet.
Some basics about Cloud Service Endpoints and Virtual Networks When we talk about Microsoft Azure, a Cloud Service Endpoint is the easiest way to access one or multiple VMs. A Cloud Service contains resources, like VMs, and it’s acting as a communication and security boundary.
This tweet from @JuniperCertify has caught my attention:
It's official...the Design track released today! Details: http://t.co/8Oz4ayOkMI Insights from a JNCDA developer: http://t.co/k8nTXGdwk1
— Juniper Networks Certification Program (@JuniperCertify) May 27, 2015 Later that day, I got an e-mail from Juniper with the same announcement. Juniper has launched its Design Certification Track inside the Juniper Networks Certification Program (JNCP) and the Juniper Networks Certified Design Associate (JNCDA) is the first available certification.
In my last blog post I have highlighted how HAProxy can be used to distribute client connections to two or more servers with Exchange 2013 CAS role. But there is another common use case for load balancers in a Exchange environment: SMTP. Let’s take a look at this drawing:
Patrick Terlisten/ vcloudnine.de/ Creative Commons CC0
The inbound SMTP connections are distributed to two Mail Transfer Agents (often a cluster of appliances, like Cisco IronPort or Symantec Messaging Gateway) and the MTAs forward the e-mails to the Exchange servers.
The next step is to connect the Synology DS414slim to my lab network. I use two HP 1910 Switches in my lab, a 8 Port and a 24 Port model. The Synology DS414slim has two 1 GbE ports, which can configured in different ways. I wanted to use both ports actively, to I decided to create a bond.
Create a bond Browse to the admin website and go to Control Panel > Network > Network Interfaces and select “Create”.
This tweet from @JuniperNetworks has really inspired me yesterday. I liked Junipers Firefly Perimeter (vSRX) from the first day. I like the idea behind this product (yes, I like everything that can be run as a VM…). But yesterday Juniper has go one better.
Introducing the vMX – the industry's only carrier class virtualized router: http://t.co/2lgXaQ1cjh #networkunlocked pic.twitter.com/V8zWvpRXoA
— Juniper Networks (@JuniperNetworks) November 6, 2014 Juniper Networks announced yesterday a virtualized and carrier-grade version of their MX Series 3D router.
The Juniper Networks Certification Program (JNCP) consists of different tracks, which enable you to demonstrate your skills with Juniper products and technologies in the areas most pertinent to your job function and experience. There are three main areas:
Junos Support Product and Technology The Junos area consists of three tracks:
Service Provider Routing and Switching Enterprise Routing and Switching Junos Security The “Service Provider Routing and Switching” track focuses on service provider and telecommunication (M-, MX-Series, Routing with OSPF, BGP, MPLS etc.
