I hope that you are not reading this blog post while searching for a solution for a failed cluster. If so, feel free to leave a comment if this blog post saved your evening or weekend. :)
Last friday, a change at one of my customers went horribly wrong. I was not onsite, but they contacted me during the night from friday to saturday, because their most important Windows Server Failover Cluster was unable to start after extending a shared VMDK.
They tried something pretty simple: Extending an virtual disk of a VM. That is something most of us doing pretty often. The customer did this also pretty often. It was a well known task… Except the fact, that the VM was part of a Windows Server Failover Cluster.… Read more
Michael White published the third release of his “What is in the bag” blog post. In reference to this, I would like to share the content of my bag.
I used a RIMOWA Salsa business trolley for several years. Unfortunately, it broke in June 2017 and a repair was refused by RIMOWA. I was very disappointed of the product quality and the customer service experience with RIMOWA.
I decided to switch to a backpack, which felt much more comfortable than carrying or pulling the RIMOWA trolley.
This is only a short blog post to document a solution for a very annoying problem. After the automatic update of my Outlook to the latest Office 365 build (version 1809), it has started to prompting for credentials. I’m using Outlook to access a Microsoft Exchange 2016 server (on-premises), without any hybrid configuration. A pretty simple and plain Exchange 2016 on-prem deployment.
I knew, that it has to be related to Office 365, because the Outlook 2016 on my PC at the office was not affected. Only the two Office 365 deployments on my ThinkPad T480s and ThinkPad X250.
To make this long story short: ExcludeExplicitO365Endpoint is the key!… Read more
It is common that vendors offer their products in special editions for SMB customers. VMware offers VMware vSphere Essentials and Essentials Plus, Veeam offers Veeam Backup Essentials, and now Vembu has published Vembu BDR Essentials.
Backup is important. There is no reason to have no backup. According to an infographic published by Clutch Research at the World Backup Day 2017, 60% of all SMBs that lost all their data will shutdown within 6 months after the data loss. Pretty bad, isn’t it?
When I talk to SMB customers, most of them complain about the costs of backups. You need software, you need the hardware, and depending on the type of used hardware, you need media.… Read more
I have worked with a lot of backup software products during my career, but for the last years I have primarily worked with MicroFocus Data Protector (former HP OmniBack, HP Data Protector, or HPE Data Protector), and Veeam Backup & Replication. Data Protector was a great solution for traditional server environments, or when UNIX (HP-UX, AIX, Solaris etc.) compatibility was required. Features like Zero Downtime Backups, LAN-free or Direct SAN backups were available for many years. But their code quality has suffered severely in the recent years. The product no longer seemed like a one-stop shop.… Read more
When taking a backup with Veeam Backup & Replication, a VM snapshot is created to get a consistent state of the VM. The snapshot is taken prior the backup, and it is removed after the successful backup of the VM. The snapshot grows during its lifetime, and you should keep in mind, that you need some free space in the datastore for snapshots. This can be a problem, especially in case of multiple VM backups at a time, and if the VMs share the same datastore.
Benefit of storage snapshots
If your underlying storage supports the creation of storage snapshots, Veeam offers an additional way to create a consistent state of the VMs.… Read more
In January 2017, I wrote an article about how to protect your WordPress blog using the WP Fail2Ban plugin, fail2ban on your Linux/ FreeBSD host, and CloudFlare. Back then, the fail2ban was using the CloudFlare API V1, which was already deprecated since November 2016.
Although the actions were updated later to use CloudFlare API V4, I still had problems with the unbaning of IP addresses. IP addresses were banned, but the unban action failed.
This is the unban action, which is included in fail2ban (taken from fail2ban-0.10.3.1 which is shipped with FreeBSD 11.1-RELEASE-p10):
This is just a short, but interesting blog post. When you have to troubleshoot authentication failures in a network that uses Windows Network Policy Server (NPS), the Windows event log is absolutely indispensable. The event log offers everything you need. The success and failure event log entries include all necessary information to get you back on track. If failure events would be logged…
Today, I was playing with Alcatel-Lucent Enterprise OmniSwitches and Access Guardian in my lab. Access Guardian refers to the some OmniSwitch security functions that work together to provide a dynamic, proactive network security solution:
Universal Network Profile (UNP)
Authentication, Authorization, and Accounting (AAA)
Bring Your Own Device (BYOD)
Quarantine Manager and Remediation (QMR)
I have planned to publish some blog posts about Access Guardian in the future, because it is a pretty interesting topic.… Read more
Sometimes you have to replace SSL certificates instead of updating them, e.g. if you switch from a web server SSL certificate to a wildcard certificate. The latter was my job today. In my case, the SSL certificate was used in a Microsoft Exchange 2016 deployment, and the NetScaler configuration was using multiple virtual servers. I’m using this little script for my NetScaler/ Exchange deployments.
When using multiple virtual servers, replacing a SSL certificate using the GUI can be challenging, because you have to navigate multiple sites, click here, click there etc. Using the CLI, the same task is much easier und faster.… Read more