After seeing these symptoms and a machine that is totally unresponsive, I chose to blindly reboot the machine, as I was running the server headless.  Not something I would ever do in a production environment, but it’s my home server.  After a reboot, the server wouldn’t even respond to ping requests, and I saw in my router that it had not registered its DHCP lease upon boot.  My obvious next step was to connect a monitor to this machine and actually see what was going on.  As I moved the machine around to plug in the monitor cable, I noticed that the steel case was warm (borderline hot, in fact) to the touch.  Once the monitor was connected, I immediately saw the root of the problem.  I was staring at a BIOS screen telling me the boot drive had failed.

Knowing what the problem was made for a clear path for recovering.  I located a replacement IDE hard drive and swapped it into the case and reloaded a stock installation of Debian 6, Squeeze.  Recreating the basic installation was no problem, and I added Webmin back onto the system.  Fortunately, I had no user data on the orignal hard drive, and I had kept the data volume in its own volume group, to avoid problems like this, should they ever come up.  The only parts of the configuration that were located on the original drive were mounting, NFS, Samba, and DNS configurations.  On the other hand, I had not gotten around to backing up that configuration to another machine to avoid such a problem.  ;-)

After getting a new boot drive with an OS on it, I moved to getting the data volume up and running.  Based upon my previous post, the data lives inside of a LVM logical volume on top of a physical RAID1 array.  Since I was simply trying to locate and re-enable an existing array, I ran: “mdadm –assemble –scan” which found the two partitions in the RAID1 and activated them.  Since they had not been touched in quite some time, no resync was even necessary.

The next step was to locate and reactivate the logical volume so that I could actually mount and use the data stored on the volume.  I ran each of the LVM *scan commands, “vgscan”, “pvscan”, and “lvscan” to confirm the metadata had been preserved.  Everything looked good, so I just had to reactivate the volume with the “vgchange -y a” command, which tells LVM to activate all available volume groups and logical volumes.  I was finally able to mount the data drives and verify that all of the expected data was there.

Now that the data drives were healthy, I had to finish recreating the lost configurations.  I added a permanent entry in /etc/fstab to mount the volume at boot, along with my NFS exports.  Also, I added the local users to the system and gave Samba passwords.  My only time-consuming task was to re-enter the forward and reverse DNS entries for my internal machines and set the DNS forwarders.

Now that the configuration was back to where I wanted it, I took the extra step of using Webmin’s backup module to export all of the configuration information from the system to my laptop.

Once I really knew what was hapenning, the fix really didn’t take that long.  I spent about 4 hours between loading the OS, reactivating the data drives, and getting the local services set back up again.  With the added knowledge of RAID and LVM recovery in Linux, as well as configuration backups, it would probably only take about an hour; most of that time would be waiting on the OS to install to the drive.

OpenOffice & LibreOffice

Arguably one of the top open-source projects in history, particularly in terms of applications for regular users, OpenOffice (and the more recently forked LibreOffice) has been well-regarded as a good replacement for Microsoft Office for most of those users. I would estimate that 85 to 90% of the features the majority of users take advantage of are available in an accessible and friendly format. The Writer, Calc, and Impress tools are comparable to Microsoft Office’s Word, Excel, and Powerpoint. Included is even a built-in PDF export tool, without the awkwardness for new computer users of a PDF printer.

PyRoom

For someone who has ADD, modern technology can be a very interesting experience, and one of distraction. Some programmers recognized this challenge and started writing tools which cut features to focus closely on the task of writing, whether it’s code or a doctoral dissertation. One of the first entries into this area is PyRoom. PyRoom starts as a full-screen program in black with a single box in the middle of the screen. This is the main interface for the program. Just below the box is a single line for information. To start, the status line offers the hint that you can use Control-H to pull up help. Other shortcuts are typically Control-[something]. There are no other distractions and no menu. This is the absolute essence of a minimalist text editor, and is available as a Debian package or a bundle of source code.

FocusWriter

After PyRoom was introduced, another group created FocusWriter on Windows. It was shortly ported to Linux and Mac, which means it could relatively easily be ported to any other operating systems. FocusWriter builds on the basic blank screen of PyRoom to add just enough features for me. It starts as a completely blank screen. If you hover over the top of the screen, the full graphical menu pulls down. At the bottom of the screen is a bad to allow you to switch between files, along with showing the word, character, and paragraph count. You can also theme the background with an image and colors, if you prefer to customize it.

FocusWriter, like I said, has just enough features for me, including:

• Cut/Copy/Paste
• Spell Checking, including while you are typing with the classic red wavy underline
• Basic find/replace functionality

There are a few other features, including a quirky preference. For those folks who appreciate nostalgia, you can turn on typewriter sounds for each keystroke. Since I prefer the older, mechanical IBM keyboards with noisy switches, it is actually a helpful feature, motivating me to write and continue to attract focus to the program.

Freemind

The fourth tool on my list will help you organize your thoughts when brainstorming. Freemind is classic mind-mapping software. Imagine back in primary school, having to write out mind maps on paper, with the bubbles connected by lines out from the middle. Freemind is a Java tool which does just that. You can use simple keystrokes, in addition to the mouse, to quickly add new nodes to the map. You can also drag and drop them around, along with expanding and collapsing any child bubbles.

Freemind is a dream when trying to organize your thoughts for any larger project or topic. As a student, I appreciate using it to plan out my papers for my English and business classes.

mGSD/TiddlyWiki/GTD Applications

My last tool is the most unusual. First, a little background:

• On the theme of focus and attention, David Allen’s “Getting Things Done�? has gotten some exposure on helping by providing a system to organize the daily tasks of work, home, and more. The “Getting Things Done�? (GTD) philosophy is gaining traction in the technology world. I would highly encourage anyone who has trouble focusing or simply a lot on their plate to look to this book to help bring everything under control.
• Some creative programmers took a wiki and made it work in a self-contained file, on your local hard drive. This tool, TiddlyWiki, uses mainly Javascript to create little miniature blocks of content that can link together, just like Wikipedia can do, but on a much smaller scale. It can easily be used as a free-form personal notebook.

mGSD is a new tool that takes TiddlyWiki and expands that to completely embrace the GTD framework from the book. You can dynamically add tasks and projects, as well as organizing these into the various areas of responsibility and contexts where we might work. You simply visit the site and download a “blank�? file. Use the Open command in your browser (Firefox is highly recommended.) and get right to work. The options can be turned on to automatically save the main wiki file, along with making a backup of the older versions of the file.

The beautiful irony of this list is that all the tools (other than PyRoom) are available as portable apps to take with you on your flash drive, if you are ever using another computer without your tools involved.  And with such an embarrassment of riches, I thought I would share my favorite tools to keep myself on-task and avoid the far-too-frequent interruptions and distractions while I am trying to work.  What are your favorite tools?  What tools have you tried that you didn’t like?  Please, leave a comment or send a message through the contact form.

The hardware you can use for this project is fairly straightforward. I used a hodgepodge of parts I had laying around. I used:

• Case: older Antec case
• Motherboard: Mini-ITX M10000N small form-factor motherboard, nearly everything integrated
• System Hard Disk Drive: IDE drive I had lying around, 30 GB

I had the bulk of what I needed for the project, but I still needed the drives and a way to attach them to the motherboard. I ordered:

• 2 SATA hard drives, 1TB, from NewEgg
• SATA Host-Bus Adapter to add SATA ports to the system from Deal Extreme
• Assorted SATA data and power cables from MonoPrice

Once all the parts arrived, I started my build. For anyone who has built a computer or replaced parts knows how simple the build really is. The motherboard is mounted into the case, along with the drives. The SATA card is placed into this motherboard’s PCI slot, and the cabling is connected. About an hour later (I removed a VERY old motherboard from this case.), I had the system built and ready for the software for the project.

Several distributions of free software could manage both the storage array and the services designed to present the array to the rest of the network. I chose to use a stock installation of Debian 6.0 stable, with as few packages installed as possible, to keep the bloat down. Of the specific software that I made sure to have installed was the SSH server, NFS file sharing services, and Samba file sharing services. After I installed Debian, I manually installed WebMin to provide a web interface for configuring everything.

First business is to create the array from the SATA disks. I used the cfdisk utility at the command-line to create a single partition over the entire drive, using a partition type of DA, which is listed as a Non-FS data partition. I then repeated the procedure for the second disk. Next, I used the webmin panel to create a RAID1 array (/dev/md0) with both of the disks. After I had the array, I created a new LVM volume group to contain the data array. Creating the volume group in Webmin requires a physical volume to be added to the newly created volume group; I chose the RAID array. Finally, I created an ext4 filesystem and waited for the disks in the array to sync. The synchronization process took roughly eight hours.

The next day, I used webmin to create some SMB shares and NFS filesystems. These will allow my Linux machines to use the data as if it were local and give access to the couple of Windows-centric devices available on my network.

With two fairly short days, and some waiting for disk synchronizing, my file storage device is complete. I am in the process of copying my data from my unreliable desktop to the device as we speak. Among my future improvements and enhancements to the configuration will be a tweaking the mounts and setting up a dedicated space for each user, instead of just a single wide-open storage space.  From the hardware side, I eventually will upgrade to a hot-swap carriage from IcyDock.  I can also add up to two more hard drives to the existing card.  As long as the drives are at least 1TB, I can expand the existing RAID1 into a RAID5.  If the drives are larger, I will create one partition as large as the partitions on the original drives.  I can then create a new partition for the rest of the new drives and create a new array.  This is, to the best of my knowledge, is the way the Drobo allows for expanding storage.

Looking closely, you can see that the people in the video are not repeated or cloned… These were actual photos taken in time-lapse using a technique and lens called tilt-shift photography to create the effect of seeing the landscape as a miniature.

There are a couple of other videos like this on the same site, one detailing a visit to Epcot and one featuring one of the Disney Cruise Line ships.

One of the first pieces that I dabbled with was setting up paging and conference calls. When I was testing conference calling, the conference would disconnect almost immediately. From my past experience with Asterisk, I know that Asterisk needs a timinig source. Most larger/enterprise PBX units would not have a trouble as they would be using an analog or digital interface card which provides the timing required. In my case, I am working with nothing but VoIP, so I have no interface card to provide a timinig source. In the past, a dummy driver is provided that can be loaded to allow Asterisk to interface with the Linux kernel’s timinig capabilities.

The only problem is that I can’t locate the module either in the directory where it should have been located or through an automated search of the filesystem. I was truly stuck. Of course, I turn to Google. Surprisingly, Google turned up no answers to where this driver could be locataed without recompiling the drivers. I am not normally hesitant to compile code, as the developers make this easy. My instincts told me there had to be a provision for handling this problem with the distribution as-is.

Fortunately, I had one more source of answers that I had in my back pocket. I fired up my IRC client and connected to the #asterisk chat room on the Freenode IRC network. The regulars there include folks who live and breath Asterisk every day, so I know the folks there have the answers I need. Naturally, after I posed my question to the room, a quick answer was offered. I needed to open /etc/dahdi/modules and comment out all references to hardware drivers, followed by a restart of the dahdi service. When I restarted the dahdi service, it reported that dahdi_dummy was loaded. Apparently, the dahdi driver assumes that if no other drivers are to load, then use the default driver to provide dahdi_dummy to allows conferences to work.

Second, I wanted to keep an eye on what calls I was making and receiving. FreePBX includes the capability on a “Reports” tab on the interface. I have also had previous experience fixing this issue. While the tool works, no data is saved to the database to search. For whatever reason, the asterisk16-addons-mysql package is not installed by default. Installing the package and restarting Asterisk allows the reporting to work as expected.

Finally, an issue occured during the initial configuration of this Asterisk system which would have prevented the saving of a new configuration. After making changes within the FreePBX interface, the administrator needs to apply the changes. When I first attempted to apply the changes I made to the system, I received an error message regarding the “retrieve_conf” script not running. Google was able to turn up the answer. By default, both the iptables firewall and the SELinux addon are activated by default. I used the built-in setup utility to turn off each of those services; the script worked immediately.

After a crazy two days of work, investigation, and both frustration and fun, my Asterisk phone system is finally where I want it. I have inbound and outbound calling on two phone numbers on a single trunk and connected to two internal SIP devices. CallerID is being sent for the correct number and I have a basic conference room setup. There are lots of tweaks and additions that I would like to make, but I think I will leave that to another entry after I have made them.

My first task was to create internal extensions and configure the phones to use those extensions. Very little trouble was had in getting my Linksys PAP2T-NA analog phone adapter to function. My Cisco 7940 is always a little trickier, just because of the provisioning capabilities. I had to adjust the FreePBX configuration to turn off NAT for that device, as my 7940 always stays here in my network. Otherwise, the configuration consisted of setting proxy information and matching secrets on the phones.

Next, I set about configuring outbound telephony service. I prefer a provider who can give service via the IAX protocol, as it was created by the Asterisk developers to compensate for some of the drawbacks of the SIP protocol. My provider, who I can’t recommend enough, is TelIAX. I configured the trunk information and it registered and came up immediately. With FreePBX, inbound and outbound routes are configured independently of trunk connectivity and each other. I set up an inbound route for my primary phone number and an outbound 10-digit dialling route.

Each of my two phones were able to make and receive calls both internally and externally. At this point, my phone system is considered usable. Finally, I can relax and take some time to enjoy the fruits of my labor. However, not everything is entirely up to my standards, a few loose ends need resolved. Stay tuned for more…

The most obvious route was to install the CD as-is. Unfortunately, this machine has no optical drive attached, and I did not feel like opening the system and adjusting the cabling to support that. I also don’t have a USB/IDE adapter. So, I first thought to use Unetbootin to install from a USB flash drive. After using Unetbootin to place the files on the flash drive, I attempted to boot to it. The motherboard supports USB floppy drives and CD-ROM, but not flash drives.

My next trick was to attempt to boot the ISO over the network, which I have successfully done with pfSense and the Debian install CD. A quick copy of the ISO into my TFTP boot directory and a modification to the PXE boot config were all that were necessary before rebooting my phone system. The PXE boot system comes up, and I attempt to boot the ISO. I was hopeful, but this worked like the rest of this install, an epic fail. Looking at the logs, I discovered that the TFTP server can’t handle serving a 650MB ISO, while it has easily handled a 60 and a 130 MB one. Another dead end, or is it?

I stepped back to think about the situation… If I can’t boot the ISO, what can I do? I remembered that when I copied the ISO to the TFTP root directory, I also copied the extracted files that Unetbootin has placed on the flash drive. I knew that PXE and USB booting, as implemented on Linux, are very similar. I configured the PXE environment to boot the extracted kernel. I was delighted to see that the installer loaded at all, after everything that had not worked as expected so far.

Once the installer started, it could not find the packages to install and asked which method to use to locate the packages. One of the HTTP. I created a new symbolic link in Apache’s DocumentRoot pointing to the TFTP root directory, making it accessible via HTTP. The installer immediately found the files and was able to install almost all of the packages. One package couldn’t be found, due to Unetbootin truncating the name. I renamed the file and clicked retry in the installer. The installer finished successfully. I rebooted and was able to log into the system.

After all of this craziness, I was ecstatic at being able to finally have a usable web interface on my phone system. Now, it’s on to configuring the system… Enjoy part 3…

At the time, the dialplans and routing all needed to be crafted by hand, in the early 1.2 days. A healthy portion of my time was involved in learning about extensions, contexts, and priorities. As I looked forward to implementing Asterisk at home, I found a fun device called the Linksys NSLU2, affectionately nicknamed the “Slug.” After attaching a 4GB flash drive, I installed Debian and Asterisk, again with a handcrafted dialplan. Fast forward another year, I had upgraded the hardware to a Mini-ITX system with a hard drive and no CD drive. Through all this time, I was hand-crafting a dialplan.

While my knowledge of Asterisk dialplans grew, several web interfaces became usable. I and some close friends tried to use the AsteriskGUI created by Digium from the original AsteriskNOW distribution. At the time, the AsteriskGUI was somewhat usable but had some significant bugs; I continued to use Asterisk with a hand-written dialplan. Since then, Trixbox was the biggest proponent of the FreePBX. Once AsteriskNOW added FreePBX as an option, I figured it was worth a try. After setting up a demo system and dabbling with it, I was pleased. My only hestiation was that the base distribution was and is CentOS, which is a fine base, but I tend to prefer Debian-based distros…

With that in mind, I have tried at least 3 or 4 times over the last few years to install FreePBX on my existing Debian-based system with its custom dialplan. Each time, I have fallen short of getting it setup. Mostly, I just haven’t invested the time to really solving that problem. In stead, I had the chance to spend the evening helping my buddy Mike learn all about Asterisk. We spent the time with the newest 1.7 version of AsteriskNOW. It was fairly clear, after some experimentation, that I needed to leverage this much more flexible tool to maintain my phone system. I tried one final time to install FreePBX on my phone system, with the same results as before, incomplete with too many holes and issues for me to spend my time with.

That night, after Mike had gone, I resigned myself to replacing that Debian base with the CentOS base of the AsteriskNOW distribution, figuring this was easier. Of course, nothing about this install was easy. I’ll share more in part 2…

I have been using the tablet off and on since then, with most of the functionality available while logged in, but there have been a few rough edges.  With a tablet PC, how do I log into the tablet while it is undocked from the keyboard?  I have used a great on-screen keyboard/handwriting recognition tool called Cellwriter.  It requires a little training, but the tool is very accurate after training.  There are two instances where a user needs to enter a password, when logging in and when unlocking the screensaver.

• Login: I use Gnome, so GDM is the login manager I prefer on this tablet.  Changing the configuration was fairly wasy.  The configuration file, in Debian, is /etc/gdm/Init/Default.  I found that a single line, added above the final “exit 0″ line, was enough to add the keyboard: “cellwriter –keyboard-only –window-x 170 –window-y 568 &” and restart X by logging out.

• Screensaver: The screensaver was slightly more difficult, requiring two steps to configure within gconf-editor:

1. Enable the embedded_keyboard_enabled key in /apps/gnome-screensaver.
2. Edit the embeddes_keyboard_command to include: /usr/bin/cellwriter –keyboard-only –xid

I could have chosen one of a number of alternative keyboards, but Cellwriter works so well and looks so clean compared to the other tools I had tried.  There are two issues that I have been dealing with with little success…

First, the –keyboard-only flag is in both locations to run the keyboard without regards to the written input.  I expected to need that during login, as GDM has idea who is logging on until after they have logged on and GDM is no longer needed.  However, I did try to use it normally with the screensaver login, and I could not get gnome-screensaver to accept my known-good password while using the handwriting portion of the application.  While I would like to be able to write my password, your entire password remains on the screen in the input box until you accept the input.  So, I will try to get at working sometime, but it probably better that i have to type my password, keeping it hidden from view.

Second, each of the applications would randomly spam one of the input buttons as I was typing on the screen.  This forces me to have to simply hit the enter key and start again.  At some point, I will have to try using the native fpit driver within Xorg.  I might already be, now that I have upgraded my system to the post-Lenny testing version of Debian (Squeeze).  I haven’t otherwise updated the system’s overall configuration in several months.

So, hopefully, I can start getting even more utility out of this again, without the encumberance of this keyboard.  As much as I would like to try one of the new netbooks, like the Acer Aspire Once or the HP Mini 1000, the lack of a touch screen makes those devices a less-attractive form-factor that this handy piece of gear.

I began investigating by looking into the metadata for the voicemails which were left; all were from unusual phone numbers outside of our area code.  My next trip was to the CDR records and my provider’s call history.  These sources showed that over 1000 phone calls were attempted to be connected through our phone system to various communities around the country.  Two patterns emerged while looking at the details of the calls:

• The calls were being generated in a non-sequential pattern; clearly an unscrupulous telemarketer was war-dialing to South Carolina, Michigan, and Virginia.
• All of the outbound calls were originating with my girlfriend’s CallerID.

So, I knew what was going on, but I had yet to determine to how this incident occured.  Further digging revealed that the Linksys ATA being used internally was lagging significantly and intermittently.  It was a moment of epiphany; I understood where the problem was, and I could take action to address it.

Several years ago, I installed an Asterisk server to provide home phone service with a company that provided an IAX trunk.  At the time, all we were using softphones to make and receive calls.  Over time, I upgraded to a Cisco 7940 for myself and an analog cordless phone on a Linksys ATA for my girlfriend.  At the time I installed the ATA, I had not used a significant amount of security of the SIP peer registration, as the network was firewalled from the Internet.

Fast forward to 5 months ago…  I obtained a business phone service through a major provider using SIP.  Due to their configuration, I was required to open the SIP and RTP ports to the general Internet and forward them to my Asterisk server.

Now, we return to the present time.  Several days ago, this telemarketer scanned my router, found open SIP ports, and began to issue a brute-force attack against my Asterisk server.  The telemarketer scanned every possible 3 and 4 digit peer name, was able to find the Linksys ATA’s peer name, and was quickly able to brute-force the password.  With this information, the telemarketer was able to register as that peer and make calls outbound, according to the dialplan configured for my girlfriend.  My Cisco’s peer was not impersonated, but it would not be likely to be responsible for outbound calling due to the unique dialplan I am using.

With the understandng of what has happened, I could work to correct and block the means by which this telemarketer was using my phone system and service:

1. I unloaded chan_iax.so to remove the possibility of additional phone calls being made.
2. I then enabled a moderate amount of security, particularly a random password for each of my SIP devices.
3. Next, I modified my firewall configuration to drop all packets through my router which contained the IP address from which the attack came.
4. I then re-enabled the IAX phone service by reloading the chan_iax.so module.

After the initial security containment, I turned my focus to handling the inbound phone calls being returned based upon the messages left with the various victims around the country.  I recorded an announcement indicating what had happened and that the compromise was taken care of.  Finally, I crafted the dialplan to play this announcement to every caller not from a local phone number.

Overall, this breach was not as extensive as it could have been, but it does illustrate that security must be vigilantly monitored and maintained.  My complacency in the security of my network ultimately led to this incident.  Fortunately, it does not seem to have led to any major financial loss to any party, including myself.