Last week I had an interesting incident at a customer. The customer reported that one of multiple Veeam backup jobs jobs constantly failed. The backup job included two VMs, and the backup of one of these VMs failed with this error: Error: Failed to open VDDK disk [[VMDS-SAS-01] VMDC1/VMDC1_1.vmdk] ( is read-only mode - [true] ) Failed to open virtual disk Logon attempt with parameters [VC/ESX: [vcenter.domain.tld];Port: 443;Login: [ADAdministrator];VMX Spec: [moref=vm-59];Snapshot mor: [snapshot-20226];Transports: [san];Read Only: [true]] failed because of the following errors: Failed to open virtual disk Logon attempt with parameters VC/ESX: [vcenter.

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.

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.

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.

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.

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.

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—–.

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.

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.

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.