Author Archives: lunger

MySQL or MariaDB and Character Sets/Collation

In MySQL and MariaDB, utf8 is not actually UTF-8 encoding. Always use utf8mb4.

To convert a table to utf8mb4:

ALTER TABLE `table_name` CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

To show character set and collation variables:

 SHOW VARIABLES WHERE Variable_name LIKE '%collat%' OR Variable_name LIKE '%character%'

References:

Connecting to a Windows 2000 Share from Windows 7

Open the “Local Security Policy” manager (can be found in the Start Menu search.

Navigate to Local Policies, Security Options.  Then find the “Network security: LAN Manager authentication level” entry and set it to “Send LM &NTLM – use NTLMv2 session security if negotiated.”.

Alternatively, this policy can be set via the command line:

REG ADD HKLM\SYSTEM\CurrentControlSet\Control\Lsa /v LmCompatibilityLevel /t REG_DWORD /d 00000001 /f

This shouldn’t adversely affect connection to Windows 7+ shares.

Source: http://www.dslreports.com/faq/16438

Update:

The setting above causes problems when attempting to connect to a remote desktop through a remote desktop gateway server (running Windows Server 2012 R2).  It must be set to the default “Send NTLMv2 Only”.

This policy can be set via the command line:

REG ADD HKLM\SYSTEM\CurrentControlSet\Control\Lsa /v LmCompatibilityLevel /t REG_DWORD /d 00000003 /f

Windows Hyper-V Errors with Backup Exec & Tape Drive

When running Symantec Backup Exec 2010 R3 with a Quantum tape drive on Windows Server 2012 R2 with Hyper-V, I discovered a problem when starting Hyper-V guests and/or managing VHDs.

Symptom

When attempting to start a VM, the VM failed to start with an error like this:

‘<VM Name>’ failed to start.

Microsoft Emulated IDE Controller (Instance ID {########-####-####-####-############}): Failed to Power on with Error: ‘A device attached to the system is not functioning.’

Failed to open attachment ‘Drive Letter:\path\Virtual Hard drivers\VMNAME_########-####-####-####-############.vhd’. Error: ‘A device attached to the system is not functioning”VM NAME’ failed to start (Virtual Machine ID ########-####-####-####-############)

‘VM NAME’ Microsoft Emulated IDE Controller (Instance ID {########-####-####-####-############}): Failed to Power on with Error: ‘A device attached to the system is not functioning.’ (0x8007001F) (Virtual Machine ID: ########-####-####-####-############)

‘VM NAME’: Failed to open attachment ‘Drive Letter:\path\Virtual Hard drivers\VMNAME_########-####-####-####-############.vhd’. Error: ‘A device attached to the system is not functioning’ (0x8007001F) (Virtual Machine ID: ########-####-####-####-############)

‘VM NAME’: Failed to open attachment ‘Drive Letter:\path\Virtual Hard drivers\VMNAME_########-####-####-####-############.vhd’. Error: ‘A device attached to the system is not functioning’ (0x8007001F) (Virtual Machine ID: ########-####-####-####-############)

This Microsoft KB article described the symptom: http://support.microsoft.com/kb/2013544.  However, the suggested solution did not solve the problem.

Cause

The KB article describes the cause as follows:

There is a timing issue with FSDepends.sys and with VHDMP.sys. This timing issue occurs when certain backup programs are installed on computers that are running Windows Server 2008. By default, the FSDepends.sys start value in the registry is set to Manual. When any third-party backup software loads its tape device driver, the software can sometimes result in FSDepends.sys and VHDMP.sys not initializing correctly.

Solution

The KB article suggests the following solution:

To work around these problems, FSDepends.sys should be set to a start value of Boot (0x0).

  • Navigate the registry to the following key: “HKLM\SYSTEM\CurrentControlSet\Services\FsDepends
  • Under the “FsDepends” key, change REG_DWORD value “Start” from “3” to “0

The rest of the solution is to also make the same change for the VHDMP key:

  • Navigate the registry to the following key: “HKLM\SYSTEM\CurrentControlSet\Services\VHDMP
  • Change the contained REG_DWORD value “Start” from “3” to “0

 

Hide Drives in Safely Remove Hardware

Navigate to the following registry path:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\msahci

Create new keys:

Controller0\Channel0
Controller0\Channel1

… and so on.

For channel you wish to keep from showing up in “Safely Remove Hardware”, create a DWORD named “TreatAsInternalPort” and set the value to 1.

Source

Bookmarklet: Dump MEGA localStorage

This is a bookmarklet that will dump the HTML5 localStorage object into a bookmarklet that you can then import into another browser.

javascript:(function(){
var key; 
var undump = ""; 
for (var i = 0, len = localStorage.length; i < len; i++){ 
key = localStorage.key(i); 
undump += "localStorage.setItem('" + key + "','" + localStorage.getItem(key) + "'); "; } 
console.log(undump);
window.prompt("Bookmarklet", "javascript:(function(){ localStorage.clear(); " + undump + "}());" );  
}());


Display Server Alias in Network Browser

“Network Places” is built from information obtained by the subnet master
browsers, which get and maintain their browse list by listening for
NetBIOS broadcasts and via periodic communication with the Domain Master
Browser (the PDC-E).

Add a REG_MULTI_SZ value named OptionalNames to the HKLM\System
\CurrentControlSet\Services\lanmanserver\parameters key and put both
names in it. Either restart the server service or reboot the system and
both names *should* show up. Eventually. (~12 minutes by default.)

Credit: Wayne Tilton