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I was forced to change my network password the other morning.  No big deal.  However, around lunch I noticed my iPhone battery life was down to 17% (from 100% at 8:00am).  I had forgotten to update my ActiveSync password on my iPhone after the change (which seemed to cause the phone to continually fail to sync my e-mail and killed my battery).  In the future, I’ll need to remember to change both passwords at the same time.

A couple weeks ago, one of our customers had their Exchange SCR copy fail due to a corrupt log file. At first we assumed that the log file was corrupted during transit to the DR site, but after recopying the log file over multiple times and attempting to restart replication, we realized the log file was actually corrupted on the source server which is a virtual machine. I had never seen this happen before and was a little surprised that the corrupt log file had not taken the mailbox database offline. With nothing to attribute the corruption to, I decided it must have been a fluke and started a database reseed the following weekend. After 3 days, the database seeding finished, but 4 hours after the reseed completed, the SCR copied failed again…another corrupt log file. [more]

I decided there must be a bigger issue. I reviewed the logs and found numerous eventid 7 errors (bad block on disk) and a few pvscsi warnings. It seemed logical that maybe the paravirtualized SCSI adapter that was being used on this virtual machine may be causing an issue…maybe it was a weird PVSCSI / Windows 2008 server problem. I had to take a break from this issue to troubleshoot another server issue for the same customer. In doing so, I had an idea…what if the physical disk is going bad, but hadn’t completely failed. Could that cause the underlying VMware VMFS partition to look fine but cause problems with virtual disk files attached to VMs. I used iLO to check out the hardware status and sure enough one of the disks had encountered numerous SMART errors and was marked “impending failure”. The array was not degraded yet because the disk had not completely failed. I have replaced the disk and will reseed the database soon, but since replacement there have been no bad block on disk errors on this VM so it looks promising.

During a recent audit, we noticed one of the Internet domain names registered to the bank was displaying a website provided by the registrar (Network Solutions).  Upon discussing this issue with the bank, they told me they had registered the name because they use it internally as their Active Directory domain name and did not want anybody else registering the public name.  So the bank’s IT vendor dutifully registered the name, but did not do anything with it as far as pointing it to an existing bank website or an “under construction” site.  As a result the registrar parked the domain name and displayed an advertisement website.  The advertisements were for Gucci, Wells Fargo, Bank of America, etc.  The bank was not very happy when they found out their domain was being used to advertise other banks.

If you have a battery powered device that you pack away somewhere in your backpack or bag, this trick might help you.  Sometimes a device will have a recessed power button, but it if is not designed well enough, you could either end up with dead batteries if it gets turn on accidentally, or no data if it gets turn off accidentally.  I have a GPS data logger that traveled around on recent trip with me so I could geotag photos.  I wanted to be sure it did not get turned off.  A good solution is to find a flat washer, or maybe two that are just the right size to go around the power button.  Glue it on carefully – you don’t want to glue the power button.  This makes the power button recessed to help prevent accidents.  Here are a couple of pictures of my GPS data logger.  I used a clear plastic washer because I did not want to occlude an LED. [more]

I recently moved a hard drive from a ThinkPad T60 laptop to a ThinkPad T400.  The hard drive had a BIOS password set, but it appeared to work normally in the T400.  I could boot, enter the hard drive password, and access the disk.  However, when I started having problems getting PGP to encrypt the hard drive, I decided to remove the hard drive password.  The T400 could not remove it – the option was grayed-out in the BIOS.  Luckily, I still had access to the T60, so I put the hard drive back in the T60 and was able to remove the hard drive password.  I have now moved the hard drive to the T400 and I am able to set/remove the hard drive password at any time.

When working with Cisco 800 model routers (and probably any Cisco Integrated Services Router) you might run into an issue that the VLAN which is assigned to the LAN ethernet ports is in an “up/down” state.  This is because an SVI must meet all of the following conditions to transition to the full "up/up" state:

• The VLAN must exist and be active in the VLAN database.
• At least one switched port in the VLAN (access or trunk) must be up.
• That port must be in the STP forwarding state.

Sometimes it is necessary to have that VLAN interface up even if there are no devices or ports using that VLAN.  [more]The most recent case that I experienced this need was when I was trying to transfer IOS images remotely across a VPN connection.  Because the transfer was traversing across the VPN I had to source the file transfer from the internal VLAN interface.   There weren’t any PC’s connected to the router so the VLAN interface was in an “up/down” state.  To resolve this issue, I could have either connected a PC or a loopback into the router or simply forced the VLAN into an “up/up” state.  Issuing the “no autostate” command on the VLAN interface will bring the interface up.  Basically, the command just tells the VLAN interface to ignore the above mentioned prerequisites.  Note: This command is only available in certain IOS images.

On Windows Server 2008, I was trying to get Java installed, but Internet Explorer kept saying that I was unable to download the file because of my security settings.  My options for changing the security zone settings were grayed out, and adding the Java website to my trusted sites did not work.  I investigated whether group policies were blocking my ability to edit the zone settings, but it turned out that there were no IE-related group policies.  It turned out that I had to run IE as an administrator (right-click and select “run as administrator”) to get access to the zone settings.

Most people know about the cookies that internet browsers use to store information.  It's easy to configure browser settings to not allow cookies, only allow trusted cookies, and to delete cookies when exiting the browser.  What slips around the radar are Local Stored Objects (LSO), also known as super-cookies or Flash cookies.

LSO’s use Flash technology to store more information than regular cookies.  In addition, LSO’s can be used to recreate, or respawn, deleted cookies.  More than half of the internet’s top websites use a little known capability of Adobe’s Flash plug-in to track users and store information about them, but only four of them mention the so-called Flash Cookies in their privacy policies according to UC Berkeley researchers.

To control these Flash cookies, you have to use the controls on Adobe’s site.  According to Wikipedia,  “Users can only opt-out of Local Shared Objects globally by using the Global Storage Settings panel of the online Settings Manager at Adobe's website. Users can also opt-out of them on a per-site basis by right-clicking the Flash player and selecting 'Settings'.  Adobe's online-only Website Storage Settings panel was created to let users view and delete LSOs on a per-domain basis. It is also possible to completely disallow LSOs from a specific domain by setting the storage space to "0 KB", however, although no data is stored, empty directories with the name of the domain are nonetheless created. Add-onextensions that allow the user to view and delete LSOs have also been created for the Firefox Web browser, e.g. BetterPrivacy.”

Using Windows Powershell, you can get timestamps for creation, last access, and last write times. 

Examples:

• PS>$(Get-Item ).creationtime=$(Get-Date "mm/dd/yyyy hh:mm am/pm")
• PS>$(Get-Item ).lastaccesstime=$(Get-Date "mm/dd/yyyy hh:mm am/pm")
• PS>$(Get-Item ).lastwritetime=$(Get-Date "mm/dd/yyyy hh:mm am/pm")

Another thing that the Powershell can be used for is setting the timestamps to whatever value you want.  It can be future or past.

Here is an example of setting the last write time of file “test.txt” to 1-1-2020:

• PS>$(get-item test.txt).lastwritetime=$(set-date "01/01/2020")