Posts

DOT1X authentication failed on HPE OfficeConnect 1920 switches

The last two days, I have supported a customer during the implementation of 802.1x. His network consisted of HPE/ Aruba and some HPE Comware switches. Two RADIUS server with appropriate policies was already in place. The configuration and test with the ProVision based switches was pretty simple. The Comware based switches, in this case OfficeConnect 1920, made me more headache. The customer had already mac authentication running, so all I had to do, was to enable 802.

HPE Networking expert level certifications

A couple of days ago, I took the HP0-Y47 exam “Deploying HP FlexNetwork Core Technologies”. It was one of two required exams to achive the HPE ASE - Data Center Network Integrator V1, and the HP ASE - FlexNetwork Integrator V1 certification. It was a long planned upgrade to my HP ATP certification, and it is a necessary certification for the HPE partner status of my employer. You might find it confusing that I’m talking about an HP ASE and a HPE ASE.

vSphere Distributed Switch health check fails on HPE Comware switches

During the replacement of some VMware ESXi hosts at a customer, I discovered a recurrent failure of the vSphere Distributed Switch health checks. A VLAN and MTU mismatch was reported. On the physical side, the ESXi hosts were connected to two HPE 5820 switches, that were configured as an IRF stack. Inside the VMware bubble, the hosts were sharing a vSphere Distributed Switch. The switch ports of the old ESXi hosts were configured as Hybrid ports.

Demystifying "Interfaces on which heartbeats are not seen"

By accident, I found a heartbeat/ VLAN issue on a NetScaler cluster at one of my customers. The NetScaler ADC appliances have three interfaces connected to a switch stack. Two of the three interfaces were configured as a channel (LAG). This is a snippet from the config: set channel LA/1 -tagall ON -throughput 0 -lrMinThroughput 0 -bandwidthHigh 0 -bandwidthNormal 0 ... bind vlan 10 -ifnum 1/3 bind vlan 10 -ifnum LA/1 -tagged bind vlan 54 -ifnum LA/1 -tagged bind vlan 55 -ifnum LA/1 -tagged On the switch stack, the port to which interface 1/3 is connected, is configured as an access port.

Azure PowerShell vs. Azure RM PowerShell

In 2014, Microsoft announced the Azure Preview Portal, which was going GA in December 2015. Since January 8, 2018, the classic Azure Portal is turned off. The “Preview Portal” was more than a facelift. The classic Azure Portal was based on the Service Management mode, often called the “classic deployment model”, whereas the new Azure Portal uses the Resource Manager model. Azure Service Management (ASM) and Azure Resource Management are both deployment models.

Security: If it doesn't hurt, you're doing it wrong!

The Informationsverbund Berlin-Bonn (IVBB), the secure network of the german government , was breached by an unknown hacker group. Okay, a secure government network might be a worthy target for an attack, but your network not, right? Do you use the same password for multiple accounts? There were multiple massive data breaches in the past. Have you ever checked if your data were also compromised? I can recommend haveibeenpwned.com. If you want to have some fun, scan GitHub for -—-BEGIN RSA PRIVATE KEY—–.

Unsupported hardware family 'vmx-06'

A customer of mine got an appliance from a software vendor. The appliance was delivered as ZIP file with a VMDK, a MF, and an OVF file. Unfortunately, the appliance was created with VMware Workstation 6.0 with virtual machine hardware version 6, which is incompatible with VMware ESXi (Virtual machine hardware versions). During deployment, my customer got this error: unsupported hardware family 'vmx-06' The OVF file includes a line with the VM hardware version.

NetScaler native OTP does not work for users with many group memberships

Some days ago, I have implemented one-time passwords (OTP) for NetScaler Gateway for one of my customers. This feature was added with NetScaler 12, and it’s a great way to secure NetScaler Gateway with a native NetScaler feature. Native OTP does not need any third party servers. But you need a NetScaler Enterprise license, because nFactor Authentication is a requirement. To setup NetScaler native OTP, I followed the availbe guides on the internet.

Meltdown & Spectre: What about Microsoft Exchange?

On January 18, 2018, Microsoft has published KB4074871 which has the title “Exchange Server guidance to protect against speculative execution side-channel vulnerabilities”. As you might guess, Exchange is affected by Meltdown & Spectre - like any other software. Microsoft explains in KB4074871: Because these are hardware-level attacks that target x64-based and x86-based processor systems, all supported versions of Microsoft Exchange Server are affected by this issue. Like Citrix, Microsoft does not offer any updates to address this issue, because there is nothing to fix in Microsoft Exchange.

Meltdown & Spectre: What about HPE Storage and Citrix NetScaler?

In addition to my shortcut blog post about Meltdown and Spectre with regard of Microsoft Windows, VMware ESXi and vCenter, and HPE ProLiant, I would like to add some additional information about HPE Storage and Citrix NetScaler. When we talk about Meltdown and Spectre, we are talking about three different vulnerabilities: CVE-2017-5715 (branch target injection) CVE-2017-5753 (bounds check bypass) CVE-2017-5754 (rogue data cache load) CVE-2017-5715 and CVE-2017-5753 are known as “Spectre”, CVE-2017-5754 is known as “Meltdown”.