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:
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.
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.
Today I changed the SCSI controller type for my Windows VMs in my lab from LSI SAS to PVSCSI. Because the VMs were installed with LSI SAS, I used the procedure described in VMware KB1010398 (Configuring disks to use VMware Paravirtual SCSI (PVSCSI) adapters) to change the SCSI controller type. The main problem is, that Windows doesn’t have a driver for the PVSCSI installed. You can force the installation of the driver using this procedure (taken from KB1010398):
Inspired by Chris Wahls blog post “Building a New Network Design for the Lab”, I want to describe how my lab network designs looks like.
The requirements My lab is separated from my home network, and it’s focused on the needs of a lab. A detailed overview about my lab can be found here. My lab is a lab and therefore I divided it into a lab, and an infrastructure part.
The developtment of the Intelligent Resilient Framework (IRF) goes back to H3C, a joint venture between Huawai and 3COM. With the acquisition of 3COM by HP, IRF capable products were integrated into the HP Networking product portfolio.
What is IRF? IRF is a software-based solution to connect multiple switches together and create a logical switching devices. The idea behind IRF is to create a logical device with one control and multiple data planes.
Sometimes it’s necessary to limit specific traffic in terms of bandwidth. Today I like to show you how to manage bandwidth limits using QoS and firewall policies. Especially if you have only limited bandwidth, e.g. a DSL connection, it can be useful to manage the used bandwidth for specific hosts or protocols. I use a really simple setup to show you, how you can manage bandwidth using CoS on a Juniper SRX.
Sophos offers a free license of their UTM firewall for private use. The product was originally developed by Astaro and since these days I use it at home. After the merger with Sophos I switched to the new Sophos UTM 9, still using my old license. I use it to seperate my test VLAN from my normal VLAN, and I use it as proxy with antivirus scanning for all my devices (iPhone, iPad, laptop etc.
