By default the Cisco ASAv has weak ssh config that many modern OS's do not support. ssh admin@10.1.10.56 Unable to negotiate with 10.1.10.56 port 22: no matching host key type found. Their offer: ssh-rsa This error is from the client side ssh client refusing to use any of the host key algorithms that are offered … Continue reading Fixing Weak SSH Ciphers On a Cisco ASAv
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CEPH: TCP Performance Tuning
Below are a few TCP tunables that I ran into when looking into TCP performance tuning for CEPH. Note that there are two separate sections for 10GE connectivity, so you will want to test with both to find what works best for your environment. To implement, we just add what is below to /etc/sysctl.d/99-sysctl.conf and … Continue reading CEPH: TCP Performance Tuning
How to Create Non-Routable Isolated (but not Private) Vlans on a Cisco Catalyst Layer 3 Switch
First off let's start out by saying that Isolated VLANs and Private VLANs are two completely different things... they are not at all the same. To a network administrator, this should make perfect sense. However, a Server or Virtualization Administrator may or may not know the different. Because of this, I hear many non-network Administrators toss around the term "Private VLAN", when they actually mean to say "Isolated Vlan", or more specifically what they are referring to is a "Non-Routable" VLAN.
Configure Syslog Logging Levels on the Asus RT-AC66U Router
How to Guide: Configure Syslog Logging Levels on the Asus RT-AC66U Router
Redhat 6 Minimal Kickstart Configuration with VMware Tools and Puppet Agent Install
Here is my small, crude, little Kickstart configuration and post install script that I have up and running in my lab at home. Don't expect to find anything too fancy here, as this Kickstart was purposefully built to be small and to the point. Here, the point was to spin up a VM, run through a basic install of CentOS/Redhat Linux, and install VMware Tools along with a Puppet agent.
Vmware CapacityIQ Unregister a Vcenter Server via the CLI
Ok two in a row, now thats strange. Anyway.. I was working on a rebuild and re-ip of my Vcenter Server as I was in the process of changing over to the Vcenter appliance, when i realized that I was going to have to lay hands on a lot of tools and change them to point/connect to my new Vcenter Server instance. Anyway. I started of with VCOPS, and I was surprisingly sucessful. So I figured I would move on to Capacity IQ.
Vmware Vcenter Operations Manager Unregister a Vcenter Server via the CLI
So my Windows based Vmware Vcenter Server went belly up again. Something to do with the SSO database not starting. Not being a lover of Windows I decided to give the Vcenter Server Appliance a shot. Install was great and I am kicking myself a bit as to why I spent so much time fighting with Windows. My new Vcenter Server, which has a different IP address then the original Windows box (might make a great Veeam server) was not registered with Vcenter Operations Manager. I was not prepared to reinstall that thing again. So I needed to figure out how to manually unregister a Vcenter instance and add register another one in its place.