T-rev's Blog

49 2018-06-21 17:40 Good free DDNS

I've been using freedns.afraid.org for dynamic DNS since 2013 and have had no trouble. I only use a simple subdomain "A" record so I can access various stuff on my home network when away from home. My router (from a prominent maker of small business network hardware) makes it fairly easy to keep this DDNS automatically updated.

47 2018-06-12 12:00 Repair of Slipping Zipper

Here's how I've repaired to like-new state many slipping/separated nylon zippers with metal zipper pull:

1.) First, you need at least few links of the zipper zipped, so if necessary do that by hand, tucking zipper teeth between each other alternating left and right (it's possible to zip the entire zipper with this painstaking process, but don't do that, as all you need for the fix is a few links), then

2.) carefully slide the zipper pull back over those links so it looks like a normal, partly open zipper. Then the magic:

3.) just firmly squeeze (front to back, i.e. inside to outside, not left-right or top-bottom) the zipper pull with pliers.


45 2014-12-20 13:01 Best Windows 8 keyboard shortcuts

The most useful Windows 8.1 desktop keyboard shortcuts for me are Winkey+X and Winkey+B

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Winkey + B activates the taskBar. Alternatively, you can first activate the Desktop, which can be done using Winkey + D (this option will also minimize all windows), and then Tab through the areas listed below to the part of the taskbar you want.

Winkey + B first activates the system tray aka notification area.
From there you can tab through in this order:
1. the show/peak at desktop button (lower right corner of taskbar)
2. the Desktop (the desktop will be active whether or not it's visible)
3. the Start Button (hit enter for the start screen, but the start menu cannot be opened by the normal keyboard right-click equivalents of context menu "app" key or shift+F10; you must use winkey+X to access the start menu via keyboard)
4. the taskbar application icons area
5a. keyboard-accessible taskbar toolbars, if any are enabled
5b. back to the system tray again, etc.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Winkey + X opens the Windows 8.1 miniature start menu, which could also be accessed by right-clicking the "start button" (windows icon at top left of the taskbar, i.e usually the bottom left of screen.

After opening the start menu, you can navigate it with arrow keys or with shortcut keys (in parentheses below). It offers quick access to:
(F) Programs and Features
(B) Mobility Features
(O) Power Options
(V) Event Viewer
(Y) System
(M) Device Manager
(W) Network Connections
(K) Disk Management
(G) Computer Management
(C) Command Prompt (can be replaced by Powershell in taskbar
"Navigation" options)
(A) Command Prompt (Admin) (can be replaced by Powershell in taskbar
"Navigation" options)

(T) Task Manager
(P) Control Panel
(E) File Explorer
(S) Search
(R) Run
(U) Shut down or sign out
(I) Sign out
(H) Hibernate
(U) Shut down
(R) Restart
(D) Desktop

44 2014-08-12 15:29 Robocopy script problem with flaky NIC

I just encountered a crazy data loss problem that had me mystified and questioning my core computing beliefs. Some of my recently modified or recently created files were being wiped to zero file size.

Specifically, the affected filename was all that remained, with a last-modified date more recent than when I had actually last modified the file. Some of my important records were being wiped out.

I have multiple copies of backups on different servers, but my strategy is mostly geared toward protecting against disk crashes or corruption, and I wasn't maintaining any file version history. Thus, if I didn't notice instances of the zero-file-size problem in time, the "newer" empty file could propagate through my backup copies, with the empty file being written over the other backup copies of the file.

I'm now pretty sure I've figured out the problem. It's a combination of a flaky gigabit ethernet port in my (9-month-old) Toshiba laptop and the structure of one of my backup scripts, which runs robocopy first in one direction and then in the other.

The flaky connection would cause the first robocopy call to fail in mid-stride. The first robocopy call at this point had already created a placeholder filename in the destination location, with the timestamp set (meant to be temporarily) to current time, but had not copied the data and actual timestamp. Subsequent to this, the second robocopy call then copies the empty placeholder back, over-writing the data in what should have been the source file!

Obviously I need to implement version history backup.

Another measure I've now taken is telling robocopy to ignore files of zero size. I added the option /MIN:1, which will exclude files smaller than 1 byte. The only (minor) downside of this is that I have some information contained in filenames of intentionally empty files, but I can get around that by giving those files some trivial content.

43 2014-01-13 13:41 Fix Samba and Windows Vista/7/8

Not sure why I didn't save this when I set up Win 7 a couple years ago. Setting up Win 8 now it wouldn't connect to shares on my NAS, and I had to search again for the setting to fix it. And the answer was a needle in a haystack of search results:

From: http://arouter.blogspot.com/2011/07/samba-file-server-on-dd-wrt.html:

When accessing Samba from a Windows Vista/7 machine, the password will
always be rejected regardless whatever you input. That's because the
Samba we used here does not support the new password authorization
scheme in Windows.

To fix:
Run secpol.msc Go to: Local Policies -> Security Options
Find "Network Security: LAN Manager authentication level" and change
setting from "Send NTLMv2 response only" to "Send LM & NTLM - use
NTLMv2 session security if negotiated"

Some Windows versions may not have secpol.msc, in this case, save
these 3 lines below to file sambafix.reg and run it:

Windows Registry Editor Version 5.00
Reboot the Windows to make the change take effect.

41 2013-03-29 04:50 How to set up your router behind an AT&T gateway

I'm trying out AT&T "U-verse". They force you to use their "Gateway" device, which is a combination DSL modem/NAT router/ethernet switch/Wireless AP. (Mine is a Motorola NVG510. The WAP seems to be a 2.4 GHz -bgn.) This is an issue for me because I have already have a (much better) router with several port-forwarding and iptables firewall rules, dynamic DNS, etc., and I had no desire to mess with my setup. I just wanted an internet connection for my existing LAN.

I was planning just to put my router in a DMZ, and a couple google probes into the topic turned up not much beyond some forum posts suggesting the same. Browsing through the router's config options, it wasn't readily apparent on the "NAT/gaming" page how to enable a DMZ, but I never had to try, because fortunately the next page was promisingly titled "IP Passthrough". The help in the margin said: "Passthrough: Allows the device's public IP address to be assigned to a single LAN client." Which is exactly what I wanted.

What I did:

1. disable the gateway's wifi
(Home Network -> Wireless)

2. disable the gateway's IPV6
(Home Network -> Configure)

3. [if necessary] change the gateway's LAN subnet to be separate from you existing LAN.
(Home Network -> Subnets & DHCP: in "Device IPv4 Address" and "DHCPv4 Start Address" and "DHCPv4 End Address" change .1. to .x. where x is your favorite number from 0 to 254)
Note: I first tried to use a 10.x.x.x subnet but it was disallowed.

4. enable Pass-Through
(Firewall -> IP Passthrough: Allocation Mode "Passthrough"; Passthrough mode "dynamic")

5. connect existing router's WAN port to one of the Gateway's LAN ports

6. unplug the power from everything for a few seconds

Everything worked immediately. I didn't change a single thing in my existing setup. I may still configure some static DNS servers, as DNS is currently being proxied through the Gateway, but it seems to be working well enough so far.

40 2012-03-10 00:13 Mystery Remote Desktop Problem

Recently I started having a strange problem with Windows 7 Remote Desktop (RDP). It always worked flawlessly before. The past couple weeks it would sometimes work, sometimes not. When it didn't work, it didn't throw out any kind of error message. It wouldn't even get to the authentication screen. The remote desktop client window would just silently close a moment after it appeared. The app on my phone would say "session terminated".

Did a little experimenting trying to narrow down what conditions corresponded to this so as to get at the cause of the problem, but it seemed almost random. So I decided to peruse the related registry entries with an eye for anything promising. Found it pretty quickly.

HKLM\SYSTEM\CurrentControlSet\Control\Terminal Server\ConnectionHandler

Within this were a few numerically named sub-keys, each of which contained a DWord named "fAcceptConnection". All but one had a value of 1. I changed the one that was 0 to 1, and I believe my problem is fixed, except for figuring out how it got set to 0 in the first place and whether it's going to get reset again (and how often)...

UPDATE: Unfortunately I have to report that the above fix did not continue to work, nor have I found a successful fix. It seems to be a security/certificate related problem...

39 2011-12-10 22:30 Fixing a Kenmore front-loader that won't spin

Had a problem with a Kenmore 417-44252500 front-loading washing machine (made by Frigidaire apparently). During spin cycle the drain pump was working, but there was no high speed spin.

Google easily found lots of people with the same problem, but ascertaining the solution was a little harder, finding manufacturer's documentation harder still. I spent enough time online over this to be inspired to type it up into the page I wish I could have found. Maybe it will be of use to someone else.

I managed to track down JPEGs of the Tech Data Sheet, which I've put in PDF here:
Kenmore 417-44252500 Tech Data Sheet
That should have been all I needed to track down the solution, but the plot thickens...

Ran diagnostics as directed in the data sheet. Everything worked including fast spin. (Fast spin only worked in diagnostics.) Checked the error code, got E47 which is "Board thinks the door PTC circuit is open during spin, refer to Test (9)." Performed the test, which consists of measuring the resistance of the PTC in the door latch. It was ~1500 Ohms, indicating a defective control board according to the data sheet (an open or shorted circuit would have indicated the door latch switch was defective).

However, after some Googling, I couldn't find anyone online for whom replacing the control board fixed the problem! I found that with these symptoms (high spin working only in diagnostic mode) it's "almost always" the door latch but supposedly still could be the (motor) control board (part # 134409900). Yet I found not a single actual report of it's having been the control board.

So with the Tech Data Sheet clearly saying one thing but no evidence to be found online in support, I remained hesitant until I found this post (thanks!) where even after passing the 1500 Ohm test, the fix still involved replacing the door lock assembly.

I got a door latch switch (part # 131763202) that was in stock nearby, and it worked.

By the way, more useful info (found on youtube) in case "you may know someone in a similar situation, or you may be in a similar situation and if you're in a situation like that..."

To remove the door latch, you don't even have to move the washer. Use a pair of needle-nose plyers to remove the spring/wire band that holds the door gasket in place, pull a bit of the gasket out of the way near the latch, remove the two screws (save them, they're not included with the replacement part), and unplug the three wiring connectors. Put it back together in reverse order (except no need for the pliers).

And, paraphrased from the tech data sheet:

To check last error code without entering diagnostic mode, turn on the machine by pushing any button, wait 5 seconds, press and hold simultaneously both Start and Pause/Cancel. After a few seconds, last error code will be signalled until buttons are released. Note that signalling of the first digit (by the Lock, Wash, Rinse, and Final Spin LEDs and audible beep) may overlap the signalling of the second digit (by the Start LED).

To enter Diagnostic mode, turn knob to Drain/Spin, then press Pause/Cancel to turn off the LEDs, then within 5 seconds press and hold simultaneously both the Option and Pause/Cancel buttons until the LEDs begin sequentially chasing.
In diagnostic mode, when knob is set to:
...Drain/Spin, LEDs chase sequentially, and pressing a button will light all LEDs in that cluster
…Rinse/Spin, hot water should enter through detergent compartment
…Soak, cold water should enter the bleach compartment
…Wool, cold water should enter the softner compartment
…Sport, door should lock
…Heavy, door should unlock
…Normal, washer should fill and tumble
…PermPress, washer should fill and spin (leak test)
…Quick, door lock, drain pump and high speed spin (DANGER, door only remains locked in this mode of diagnostics, and may be opened while drum is still spinning after performing this diagnostic!)
…Delicate, last error code will be signalled

38 2011-12-02 12:34 Wake-on-LAN Dell Dimension 8300 PCI Card

I've long been using WOL (Wake-on-LAN) with my Dimension 8300's integrated fast ethernet (100 Mb/s) adapter. I was using BIOS version A01, and WOL worked fine with no special BIOS settings.

Aside: I used to have a gigabit PCI card, but needed the PCI slot for something else and, besides, hadn't upgraded the rest of my network to gigabit and thus had not much use for it (other than when I'd used two NICs at the same time occasionally, for ICS (Internet Connection Sharing) or for configuring network hardware).

Anyway, I've upgraded to gigabit and WOL didn't work with my WOL-capable PCI NIC. It seemed the motherboard was capable, as my switch still showed the NIC connected at 100 Mbps with the computer shut down (though no LEDs lit on the NIC).

Upgrading BIOS to the final version A07 (10/1/2004) didn't fix WOL (although, by the way, it did seem to fix the problem of USB keyboard working in GRUB only from reboot and not from cold startup).

The following, however, worked like a charm. First my notes:

from http://telement.wordpress.com/2010/06/14/dell-dimension-8300-wake-on-lan/

Dell Dimension 8300 wake on LAN
2010 JUNE 14, 15:27 +8
How to allow the Dell 8300 to power up from hibernate and power off mode when receiving a Magic Packet via the network card, in Windows XP Pro SP3.
Dell Dimension 8300, BIOS A07 (circa 2003/2004)
on board Intel PRO/100 VE Network Card
*Disclaimer: The following instructions are provided without any warranty. Please do it at your own risk. The writer is merely sharing what worked for him, and your milage may vary.
To allow the 8300 to wake up from a hibernate (S4) or power off (S5) state, check the following:
  • Search for DCCU (Dell Client Configuration Utility) at Dell - http://support.dell.com/ (The DCCU version tested here was 3.1)
  • Install and run it in Windows XP, set the following:
    WakeupOnLAN 6 = Enabled for all NICs
    *Recommended to change this item alone only. Leave the other settings untouched to prevent accidentally messing up your BIOS. This item is DISABLED by default, and it is NOT visible in the 8300 BIOS.
  • If you do an Inventory reading (using the DCCU) of your 8300 BIOS, theWakeupOnLANMethod should be 3 (Magic Packet), and is unchangable (Just have a look to confirm).
  • After setting the above WakeupOnLAN value 6, create the SETTING executable with the DCCU. Then run it. It will update your BIOS on-the-fly in XP.
  • Perform a reboot after this. Go into BIOS.
  • Check to ensure in BIOS > Power Management > Low Power Mode is DISABLED. (The BIOS help for this item says if left enabled, it will not power up from hibernate or off). Save BIOS settings and exit.
  • Boot into Windows XP.
  • In your Network Card Properties, Power Management tab, check Allow this device to bring the computer out of standby. Click OK to close the windows.
  • You’re done. Put it into hibernate or shutdown, and the LAN lights should be still on (so will your network router’s indicator lights for the PC).
  • Test it using another PC, with Magic Packet tools from http://www.depicus.com (Great Site!)

Extra Titbits
The 8300 have a soft power function. Meaning when in a power off mode (S5), it can be started by software.
Try this little fun exercise:
  • Open up Start > Program > Accesories > System Tools > Scheduled Tasks, set it to run theCalculator program, five minutes from your current time.
  • In the SETTINGS tab, tick the box marked Wake the computer to run this task.
  • Click OK and shutdown your PC.
  • Sit back and enjoy seeing your 8300 come alive in 5 minutes, all by itself. Pure magic!

37 2011-09-12 03:30 Tonight's commute

i've been biking to work even more often. it's not a bad commute: only four miles one way (though there are some hills that are a lot more significant than flat miles). usually i take either the most direct way (all on roads, including busy 5 lane road) or a route that makes use of fayetteville's bike trails (then i just have to cross the busy road).

probably the main reason (psychologically) i like to bike is that it's more interesting/adventurous. (there are logical reasons too: exercise is healthy, saving a bit of gasoline, being a bit green. by the way i work for a green bio-energy company, so saving gas feels in the right spirit.) it feels more like i've accomplished something by getting to my destination. these are basically the same reasons i used to ride an 80cc honda before it broke and i took it apart without fixing it...)

i got a mountain bike last winter, and it's what i've been commuting on. it's not particularly well suited to paved roads, so i've been shopping for a dedicated commuting bike. but this reminded me that i haven't actually been mountain biking a lot lately. i think it's fair to blame this mostly on the super hot summer we had. i biked early in the morning a couple times during the summer, pulling my 3-year-old with her bike attached to mine. the last time went off-road was july 9.

anyway, the nice weather is here now, so i thought it was time for some mountain biking. so when i left work at 12:30am, i headed in a different direction. after one large hill i stopped at a walmart neighborhood market for some AAA batteries, as my helmet headlight was getting a bit dim. (it was my first ever time in this store, as i've boycotted it on principle ever since it was put in right across the street from another fairly new grocery store.) i walked right in with my bike, since i don't take a lock to work, and i seemed to be the only customer. one checkout was open but i had to find the cashier nearby.

then it was on to lake fayetteville under a full moon. i encountered maybe three dozen very surprised deer while on the paved part of the trail, followed by varied other fauna. then i turned on my headlight and veered into the woods. at the bottom of the first hill i stopped short twenty feet from a skunk. he did begin to retreat, but he was staying on the trail, and of course going much slower than i wanted to. after a minute or so of shining my light at him and ringing my pedestrian-alerting bell, he finally moved off the trail. in fact, he was out of sight, and i couldn't tell exactly where he was, though i was pretty sure he was still within eight feet of the trail. i took my chance and zipped past before he could do anything about it. it worked out ok.

after this, and maybe worst of all, were a series of big spider webs (and occupants) that i could see a fraction of a second in advance, just enough time to mostly duck under most of most of them. i say worst because ducking your head that fast (keep in mind i'm wearing a bike helmet with an LED headlamp strapped to it) is rough on the neck. actually, the downward motion is fine; it's the stopping of the downward motion that's rough. i may feel that tomorrow.

(i'm sure this little jaunt was nothing compared to k-ro's many muddy cambodian nightime rides.)

anyway, then it was on to another walmart for some groceries. again, no lock, and by now it's 1:30am, so i again propped my bike just inside the door (which is by the produce, which was what i wanted), but this is not just a neighborhood market, there are actually some customers and quite a few employees in sight one of whom informs me that i can't leave my bike there. i say, ok, i won't, and wheel it on into the store with me. they didn't have a single piece of organic fruit. but i grab a few things, and since my bike is safely with me i feel ok going all the way to the peanut butter aisle near the back. i check out and still get home at the same time that i did after having to stay late at work yesterday.

reminds me of a midnight ride or two (and numerous runs) that phil swope and i went on in college. on one, i hit an unseen hole in the road at high speed, had to bail off the seat, and, still holding the handlebars, skated down the road on the metal cleats attached to my bike shoes, no harm done. maybe i was little lucky there. but a couple more miles out, near the city limits, my free wheel broke, and i had too push the bike back to the dorm like a scooter.

also reminiscent of when i road to west fork at night on the not-yet-paved I-540. with no light that time. and a light-less, moon-less hike a couple miles through the woods as part of a "bachelor party". and a lightless cave exit (best way to avoid both falling and head-bumping is to crawl backwards). interestingly memorable, this category of activities.