Migrate Paravirtualized Xen to KVM under RHEL
Update July 11, 2009: Re-registering VMs at RHN uses an extra entitlement with RHEL5.4Beta
Update July 15, 2009: Swap usage, clock and disk cache of the virtual machine
Update July 16, 2009: Replace virsh create with virsh define & start to create a managed domain and not a transient one
Update September 2, 2009: Re-registering with RHN works
Update September 2, 2009: RHEL5.4 has been released. Added a note about services on the physical host
Update September 6, 2009: Updating TimeKeeping and Hugepages
Canned Meat
Preventing Spam e-mails is so easy and yet, because a seemingly substantial amount server admins refuse to read up on the standards, so very hard. For instance, when you try to implement all the measures at http://calum.org/posts/postfix-antispam, you'll find that a substantial amount of legitimate mail is refused by your mailserver. When I tried here in the Netherlands, almost 25% of all mail was rejected. I am talking about a seemingly amount of admins, because often it is not the admin who is to blame, but the ISP.
Get Thin
I'm evaluating Suns SunRay technology for several customers at the moment. The SunRay is a very dumb graphical terminal requiring only between 3 and 4 watts of power. The desktop environment is running on a central computer. This can either be a virtual machine per user (VDI) or a multi-user operating system like Linux. (suggested reading before this blog)
Fedora 10 RAID initialization problem
We interrupt this boring strings of blogs for some real news.
Does TCP/IP have a future?
Network Convergence is a hot topic nowadays. This is driven mostly by storage networking. The first products which can deliver Fibre Channel over Ethernet (FCoE) are starting to appear even now. There are a couple of drivers for developing Ethernet for storage networks:
- Ethernet development is ahead of Fibre Channel and Infiniband in terms of speed
- Common network layer simplifies infrastructure management
- Reduction in the number of network interfaces and thus initial hardware cost
Back to Square One
In 1992 when I started my study in Astronomy, most students at the physics department were using X-terminals. Workstations were still fairly expensive then and had more power than any one person needed (on average). The X-terminal was a fairly dumb device. It had an X server for graphical representation and tftp client for booting. They worked very well in combination with UNIX servers.
Virtualisation Tips III
In the previous 2 blogs, the soft side of virtualisation was touched. This part is about the real stuff (no offence to non-techies meant). Though this part is technical, there are some tips to save money below, so non-techies may want to read this as well.
Virtualisation Tips II
At the introduction of virtualisation in any organisation its impact on service management is often overlooked. Virtualisation is implemented as just another technology. To gain maximum profit from virtualisation changes in the way services are managed are needed. Something, that became clear already in "Virtualisation Tips I". Changes in processes and procedures might even be necessary to remain legally compliant. If cost is the main driver behind virtualisation, the systems management approach is absolutely critical. Not only in processes and procedures, but also in tooling.
Virtualisation tips I
The human factor is often overlooked when implementing new technologies in the data center. Most organizations do think about training their personnel and most actually do spend budget on that, but that is it.
Switch Mishmash
Last week, I stumbled upon an interesting problem. One of the projects I'm working on as an astronomical sensor grid, putting out about 2.6Gb/s of data per sensor station, coupled to a central super computing infrastructure. This system is still in the buildup/tender phase, so the network consists of networking equipment of various brands, to test out what the differences are and how well they work together. There are only 5 sensor stations at the moment, so the total amount of data is manageable. In the future the total data stream will grow to about 1Tb/s, to be processed real time.
