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Notes from MerriLUG: Christoph Doerbeck: Xen on RHEL5

By Ted Roche on April 25, 2007 in Home Page, Linux, OpenSource, Technology

Thirty people attended the April meeting of the Merrimack Valley Linux
User Group, held as usual on the third Thursday of the month at Martha’s
Exchange in Nashua.

Heather did a fine job of welcoming the large crowd, listing some
upcoming events (remember, you can always find them on
http://www.gnhlug.org), and requesting feedback on next month’s topic: a
professional graphics designer has offered to discuss what’s available
in Linux for graphics, but wants feedback on what to focus on: removing
red eye from photographs, structured drawings, etc. Let Heather know
what you’re looking to do with graphics in Linux.

Christoph was the main presenter. He is a Sales Engineer with Red Hat
and has quite a history with Linux/UNIX. He arrived with three laptops
and his own gigabit network to demonstrate several configurations of
virtualization. One laptop lacked the new hardware support and was
relegated to running VMWare. The other two machines (an HP with an AMD
chip with the magick SVx bits, and a “StinkPad” – his term, not mine! –
with the Intel VTx/VTi capabilities) were capable of using Xen with full
or para-virtualization. Christoph demonstrated both, and used the three
machines to show how a virtual machine could be transferred from one
machine to the other. Suspending and moving the VM was not successful
(it’s a demo, these things never work), but the harder one, moving a
running session was successful, demonstrated vividly with a running
video on his controlling machine streamed from a server that started on
one machine and finished on the other. Bravo!

There was also a discussion of the other alternative for virtualization,
single-kernel-image virtualization, where multiple sessions are running
in multiple zones, somewhat like a “chroot jail.” Examples of this kind
of VM include Solaris Zones, Virtuozzo and Open VZ. Members of the
audience contributed insights to some of the other projects going on,
such as the KVM (Kernel Virtual Machine) project favored by some of the
kernel developers, UML (User Mode Linux) and others.

Christoph wrapped up with a long and thorough question-and-answer
session. He then offered a completely different topic: he mastered a DVD
with menus, music, video overlays completely in Linux and had some clips
to show off. A general consensus was that he was welcome to come back at
his convenience to talk about that, too!

Thanks to Christoph for the great demo, to Heather and Jim for
organizing the meeting, to the folks at Martha’s Exchange for providing
the facilities, and to all for attending and participating.

Thunderbird 2.0 email client goes gold

By Ted Roche on April 23, 2007 in Home Page, Linux, OpenSource, Technology

DesktopLinux.com relays the news that the Thunderbird 2.0 email client goes gold. ‘Way cool. Looking forward to trying this out. I’ve been using T-bird 1.x for quite some time now, and it’s moved to becoming my primary email client, edging out Safari on the Mac and Evolution on the Linux platform. Mozillazine points out more information, including release notes and feature lists. Now, this is a Two-Point-Oh release, and my advice to the conservatives would be to hold off for the Two-Point-Oh-One version, or at least until a patch or two comes out, if you’re not comfortable installing and uninstalling mail clients. Make a backup, of course. Note that Linux clients have a funky problem with spaces in the path, so avoid spaces.

Red Hat Magazine: “Risk report: Two years of RHEL4”

By Ted Roche on April 21, 2007 in Home Page

Mark Cox writes in Red Hat Magazine, Risk report: Two years of Red Hat Enterprise Linux 4
“Red Hat® Enterprise Linux® 4 was released on February 15th, 2005. This report takes a look at the state of security for the first two years from release. We look at key metrics, specific vulnerabilities, and the most common ways users were affected by security issues. We will show some best practices that could have been used to minimise the impact of the issues, and also take a look at how the included security innovations helped.” The article not only provides some interesting information on Linux security; it also gives some insights to how the folks inside Red Hat view the security issues.

Seat Belts

By Ted Roche on April 16, 2007 in Home Page, Personal

New Hampshire’s legislature is considering a mandatory seat belt law as New Hampshire is Last in the Nation on this requirement. In this morning’s Concord Monitor, Eric Moskowitz points out that “Belts may save more than lives: Insurance costs could drop.” Yeah. maybe, but there are better reasons. Garrett Fitzgerald links to a post by Jim Macdonald:

“Do you know how we can tell the difference between people who were wearing their seatbelts and those who weren’t, at the scene of an automobile accident? The ones who were wearing their seatbelts are standing around saying “This really sucks,” and the ones who weren’t are kinda just lying there.”

Don’t be found lying about. Wear your seat belt. Whether required by law or not.

Garrett Fitzgerald: Mas FoxPro

By Ted Roche on April 10, 2007 in FoxPro, Home Page, Microsoft, OpenSource, Personal, Technology

Garrett Fitzgerald blogs Mas FoxPro: “In view of Microsoft’s decision to abandon future development of Visual FoxPro, there is a movement afoot to ask MS to open-source the product, so the community can take it forward. If you’d like to see this happen, one thing you can do is sign the petition that PortalFox is running.”

It’s an admirable notion, but just because Microsoft doesn’t want to continue development, doesn’t mean they are willing to turn their tools over to a potential competitor. That would be altruistic.

There’s no doubt the software contains all sorts of embarrassing comments, perhaps undocumented calls to APIs Microsoft doesn’t want others to know about or use and probably some ugly work-arounds. It would be very educational to read the source and understand some of the obscure behaviors of FoxPro: where the phantom record really hides, how “Workarea Zero” works and why Error 14 reports Error while reporting Error 14, but I’m afraid the final journey of Visual FoxPro code will resemble the final scene in Indiana Jones, with the crate of source code wheeled back into the misty distances…

UPDATE… ComputerWorld covers the petition with an article that covers the history of FoxPro better than any other I’ve ever read in the trade press. This is the best press FoxPro has gotten since PC Magazine gave it the Editor’s Choice award, and that was some time ago.

MerriLUG, 19-April: Christoph Doerbeck, Xen on RHEL5

By Ted Roche on April 9, 2007 in Home Page, Linux, Technology

A not to be missed presentation: the Merrimack Valley Linux User Group will host Christoph Doerbeck of RedHat presenting “Virtualization on Linux,” a live demo of the Xen technology running on Red Hat Enterprise Linux 5. Details here. Reservations are strongly encouraged for dinner: we’ve had a couple of huge showings at MerriLUG lately, and the staff at Martha’s have been very accomodating at getting everyone fed and on time for the meeting. I suspect this one could be SRO also.

DLSLUG notes, 5-Apr-2007: Todd Underwood discusses ZFS

By Ted Roche on April 8, 2007 in Home Page, OpenSource, Technology

Fifteen attendees made it to the April meeting of the Dartmouth Lake
Sunapee Linux User Group, held as usual in Carson Hall at the Dartmouth College campus on the first Thursday of the month.

Todd Underwood, Vice President, Operations and Professional Services at Renesys presented “ZFS: The Last Word in File Systems.” Renesys is in the business of collecting, analyzing and archiving data about what’s happening on the internet and, not surprisingly, that’s a lot of data and growing geometrically. One of Todd’s projects is to provide fast and reliable storage for the hundreds of gigabytes per day acquired and the tens of terabytes of data stored. He presented a survey of what’s out there, what his needs were, and how he reluctantly narrowed the search down to SUN Solaris and ZFS. While he had nothing but praise for ZFS, he expressed some reservations about SUN. Strong reservations.

Todd dug into the ZFS architecture. ZFS is truly amazing: disk contents are always coherent, with writes all checksummed, writes as atomic transactions, with “fancy FS internals” like IO scheduling, dynamic block sizes and prefetch queues, huge limits (128-bit data). ZFS flattens the Linux file system model of multiple layers into a single monolith, and eliminates entire classes of problems introduced by the multiple layer architecture. There is no fsck. Devices are accumulated into pools. File systems are assigned to pools. Storage addition and maintenance is fairly trivial. ZFS performance is remarkable, at disk speed (with compression, sometimes in excess of disk speed).

Todd presented the rough outlines of his storage system: $17k worth of hardware from SUN and Dell yields 7.5 terabytes of storage with nearly a gigabyte per second throughput. Todd’s disk storage challenge is solved, as the company’s demand can’t match the throughput capacity of his system, for now, and the system can be expanded with additional external storage.

As for the porting of ZFS onto other architectures, Todd expressed the opinion that running on Solaris or OpenSolaris is likely the best current solutions. Porting onto BSD is underway but not yet ready. He had heard that ZFS was ported to OS X but could not confirm (Googling ZFS OSX yields interesting results).

Todd promises to send along slides from his presentation; I’ll try to post links to them to the website.

After the main presentation, there was a good session of questions and answers. I asked a question on replication of Postgres and Todd recommended the Sequoia product.

Thanks to Todd for his thorough presentation, to Bill McGonigle for organizing the meeting, to Bill Sconce for sharing his notes with me for this post, and to all for attending and participating. Next meeting, still tentative, will be on writing a FireFox extension by Roger Trussell.

Notes from CentraLUG, 2-April-2007: Bill Stearns on LVM

By Ted Roche on April 3, 2007 in Home Page, Linux, OpenSource, Technology

A great meeting last night. The Central New Hampshire Linux User Group met at the usual place and time: The New Hampshire Technical Institute‘s Library, Room 146, 7PM on the first Monday.

I did my usual rounds of announcements, Shawn O’Shea pointed out that besides for the discuss and announce mailing lists, you can also subscribe to the lists via RSS by using one of GNHLUG’s archival sites. Add one of these to your favorite RSS readers to see the GNHLUG announcements: mail-archive.com or gmane.org

Everyone got to introduce themselves and speak a little bit about what they’re up to. I passed around a couple lists of topics and speakers from the wiki to find out what the attendees want to see for future sessions.

Bill Stearns presented “LVM: Logical Volume Management.” He explained about the basic need to expand or re-allocate disk resources without making hard partition changes, in some cases without even shutting down. We started right in on an exercise: using the loopback device and some spare space in /var/tmp, we created three loopback block devices. We assigned them as PVs (Physical Volumes) and allocated two to a Volume Group. Then, space could be allocated out of the volume group to provide the space needed. Additional PVs could be added to the VG, additional space from the VG could be allocated to a mount. We had a good discussion about the choice of filesystems and the different processing required for ext3, reiser, xfs, jfs file systems – most of which can be resized when on-line. (Bill recommended the MythTV HOWTO for a good discussion of which file system to use.

We had a good side conversation at this point about the mount tables and the significance of several flags Bill had. An intesnse discussion of ‘noatime’ – useful for hierarchical file management, but generally of little use, and a lot of disk activity, power consumption, speed decrease, and for FlashROM devicers, perhaps lifetime shortening can be avoided by adding noatime to the mount tab. Bill also had war stories about the security implications of nodev and nosuid both of which are a good idea for insertable media unless you have a specific reason for needing them.

We finished up the LVM exercise by adding the third PV to the VG and then resizing the ext3 partition to include the space. Bill took questions from the audience: one lady had just installed LVM on the Linux partition on her mainframe (!) that weekend, and wanted to know more about LVM striping. Other questions on reliability, use with RAID. Bill had some pointers for adding additional storage: use of USB2 (not USB1!) external drives (Bill hasn’t been happy with Firewire storage on Linux) or using an external storage solution (he mentioned CoRAID which uses rackable ethernet-to-ATA raw drives; Bill had one sample to play with) and handled some questions further afield, like the file defragmenter Bill has on his site.

Yet another great LUG meeting. Thanks to Bill Stearns for the great presentation (and 3-ring-bound handouts) and providing the raffle door prizes. Thanks to Bill Sconce for providing the projector and doing the note-taking during the meeting. Thanks to the New Hampshire Technical Institute for providing the facilities.

Look forward to a great presentation on OpenWRT by Ben Scott at the May 7th meeting (where you can expect him to be heckled) and another great presentation on Drupal by Seth Cohn on June 4th. Hope to see you there.

Life After VFP

By Ted Roche on April 2, 2007 in FoxPro, Home Page, LAMP, Linux, Microsoft, MySQL, OpenSource, Personal, PHP, Python, Technology

Robert Jennings posts Yet “Another Life After VFP Thread.” For those not following VFP closely, MS recently announced a confirmation of earlier news that there were no plans for a VFP version 10, and that the VFP scripts in the project known as Sedna would be released under some sort of public license. Poor communications lead to media and Slashdot reports that VFP was to be Open Sourced, sadly not the case.

Robert does a good job of outlining the huge cost in moving a vertical-niche application into another development environment, language and runtime. Most sophisticated specialty applications have person-years of investment built into them, knowledge not easily extracted, transferred or translated to any new environment. Regardless of whether that new environment is Dot Net, Dabo, LAMP, Python or Visual Fred, there will be a huge cost and risk with any enterprise making this switch.

Unlike the Open Source world, when a vendor choses to discontinue a product, developers have little choice but to move along. While many folks point out the upside that the product will likely run for years to come, and a lack of Microsoft official support doesn’t instantly obsolete a product (DOS apps can still be found, after all), there is an immediate slowdown in the custom software market, and a longer-term turning away from the product by customers. Large-scale vertical products have to be operating with 5- and 10-year plans for reinvestment and changes in direction, to ensure they can fund “The Next Big Thing” while continuing to deliver good value to their customers today and tomorrow.

This is not a death knell for the product. The writing has been on the wall for years. But developers with large applications have to be looking around for a new platform.

FoxPro developers always viewed themselves with a bit of “Battlestar Galactica” mythology: a rag-tag crew of self-taught developers from the PC Revolution, they survived the dBASE wars and the implosion of Ashton-Tate. Working under a cruel master who never promoted their product, they persevered. MS’ internal team developing VFP did amazing things on a shoestring budget, introducing a fairly smooth transition from procedural to object-oriented, from developer-guided to event-driven interfaces, from characters to pixels, from local ISAM to RDBMS. The VFP IDE was a remarkable environment in which to develop rich-client, component-based, web-driven or even server-based applications. I will miss it, and look forward to becoming as skilled at my next platform.

DLSLUG: April 5th: Todd Underwood: ZFS

By Ted Roche on March 30, 2007 in Home Page, Linux, OpenSource, Technology

Bill McGonigle announces the April meeting of the Dartmouth – Lake Sunapee Linux User Group. The main presentation will be “ZFS: The Last Word in Filesystems, ” presented by Todd Underwood, VP of Operations and Professional Services, Renesys Corporation. Here’s the pitch:

ZFS is the most original work in storage management in years. It offers a revolutionary, integrated approach to block device, raid, volume management and filesystem technology. We’ll take a high-level look at what makes ZFS so different from previous storage technologies and look at efforts to port ZFS to free operating systems (ZFS is available for FreeBSD and in a userland port to Linux, but the path will not be easy).

Todd has with more than 10 years experience in architecting, building, and supporting large-scale distributed systems. Before Renesys, Todd was senior vice president and chief technology officer at Oso Grande Technologies, the largest Internet service provider in New Mexico, where he was the lead consultant in the security practice. Before that, Todd was chief technology officer at Lightdart Managed Data Centers, a co-location and hosting start-up built in partnership with Public Service Company of New Mexico. As a graduate student, Todd led the effort studying high-speed networking for large-scale computer clusters at the University of New Mexico. Todd holds a B.A. from Columbia College, Columbia University and an M.S. in computer science from the University of New Mexico.

Looking forward to the meeting. Hope to see you there!

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