Category: Data Center

Corruption in dlmalloc 0

Server Hardware / Server Virtualization

ESXi Fails with “Corruption in dlmalloc” on HPE Server

“Corruption in dlmalloc” issue occurs because multiple esxcfg-dumppart threads attempt to free memory which has been used for configuring the dump partition. Thread A checks if there are entries to be freed and proceeds to free them, while within the same time frame, Thread B is also attempting to free the same entries.
Based on VMware KB2147888, this issue is resolved on ESXi 6 U3. But why issue is happening on ESXi 6 U3 or ESXi 6.5 U1 when they are installed on HPE ProLiant servers?

0

Server Virtualization

How to Export Big Virtual Machine (>2TB) as OVA or OVF

I guess, you know the instruction but let’s quick review. You can export virtual machines via some different tools such as vSphere Client, vSphere Web Client and others. All administrators do it today and familiar with OVA and OVF. It’s possible to export small virtual machines via vSphere Client, vSphere Web Client, PowerCLI. If you want to export virtual machine with 200~300 GB virtual disks (Thin or Thick), there is serious problem, just make sure that you have enough free space. But did you try to export big or monster VM as OVA or OVF?

VNX Domain - Unverified Systems 2

Data Storage / How To

VNX 2 Series: Best Solution to Remove Unverified Systems

VNX Storage arrays can be added to a domain for centralization logging and management for multiple storage arrays. Also Unisphere Central can be added to a VNX domain.

Sometimes, storage administrator makes mistake about adding or removing VNX storage arrays from VNX domain. As an example, administrator has to remove a VNX for send to repairing but forget removing storage array from domain. Another example, when there is multiple domains with multiple range of IP addresses, may be administrator add array to domain wrongly and after that, change IP and add to another domain.

In these situations, domains will contain some systems as unverified system, the unverified systems should verify again and otherwise should be removed.

Linux Container 0

Reviews / Server Virtualization

Operating System Level Virtualization (Part 2) – Implementations Comparison

These days, everyone knows what’s Cloud Computing and cloud based services are using for speedup deployment of organizations services. Operating System Level Virtualization or Containers helping system architectures and administrators to achieve the goals. There are many implementations for containers that today, those methods are compatible with different hardware architectures and operating system.

You may know that Unix has OS Level Virtualization from past years and this technology is very older than other virtualization such as Full Virtualization or Paravirtulization.

Full Virtualization (VMware ESXi, Hyper-V) and Paravirtualization (Xen, UML) provides different guest OS but there is no way to use different guest OS when you are using containers. Of curse, some solutions are under development.

1

Operating System

NTP Software Implementations Comparison

This post is about NTP Software implementations actually, but I have to write some words about NTP. NTP is an angle for financial applications, actually some of services such as banking services are very depended to clock synchronizations protocols. NTP is an ancient thing, it is more than 30 years old and even older than Windows 7 and Windows XP.