This is not really a blog post more a note to self. After pulling my hair out because after an update of the X-server and Gnome on my Fedora 20 box every font accross windows, window titles, app-screens more or less became unreadable blurry and fuzzy characters all over the place that were only readable […]
This is important!! Now, you would think that when you look at the weather channel and the person tells you there is a wind coming from the North the direction is from North to South. This could be interpreted somewhat different when he or she tells you there is a \”northerly\” wind. Does the later
Brocade 65xx series and airflow Read More »
The FC frame header has not changed since its inception back in the late 80-ies. This shows the absolute rock-solid backward compatibility towards previous generation platforms and vendors. Obviously the the FC protocol itself has grown and evolved with marked demands to provide an extremely flexible transport mechanism for the most demanding storage environments. When
FC Frame header, or is there more to it Read More »
Well, almost… 32GFC is fixed and at the standard has been ratified and the physical specs are moulded in concrete. In addition to this there are functions that enable to combine 4 of these into a single 128Gb link. Yes 128Gb/s. That\’s fast….Ohhh wait… thats only ONE WAY which means a single link can push
128GFC Fibre-Channel is here Read More »
The board of Microsoft has appointed a new CEO. When Steve Balmer announced stepping down from one of the worlds most influential companies for the last 3 decades the search began. You can say from Microsoft what you want but it has been the company that not only brought computing to the home but also
Microsofts new CEO. Saviour or the same? Read More »
OK, let me make one this clear, and most of you know this already, I\’m not a fan of FCoE and I wrote numerous articles around this topic. I work for a vendor especially focusing on storage connectivity in a engineering support role. Basically it means I need to know this stuff. When I see
Comparing different technologies Read More »
In Fibre-Channel, and many other network protocols, the use of CRC (Cyclic Redudancy Check) is adopted to detect corruption of frames. Be aware of the word \”frames\”!! As I explained in previous posts there are two layer of link integrity, an 8b/10b encoding/decoding algorithm (on 10G and 16G FC it has been changed to 64/66)
For numerous years entire bibles have been filled with storage design concepts, pro\’s, cons, benefits, cost structures on port-counts vs. performance etc. however whenever I get to see a fabric overview of what is connected to what and how stuff goes back and forth between initiators and targets it always (well around 99% of the
Fabric design, the good the bad and the ugly. Read More »
Linux has been pretty good with and for storage. The sheer volume of options w.r.t. filesystems, volume-managers, access methods (FC, iSCSI, NFS, DAS etc), multi-pathing but also the very broad support of the hardware ecosystem is something to be proud of. The issue with storage support is that you ALWAYS have to maintain a massive
Why partition alignment on disk matters (Linux) Read More »
The storage world has always been predictable (from a technical side that is. :-)) This means that data coming from an application through server and traversing a multitude of connected devices to a spindle (in whatever form or shape) takes the logically shortest, fasted and best available route. These routes are calculated based on a
Dynamic Load Sharing (DLS) and In Order Delivery (IOD) Read More »
