DNS Records

DNS Records

Record Type	Description	Function
A	Address record	Returns a 32-bit IPv4 address, most commonly used to map hostnames to an IP address of the host.
AAAA	IPv6 address record	Returns a 128-bit IPv6 address, most commonly used to map hostnames to an IP address of the host.
CNAME	Canonical name record	Alias of one name to another: Canonical records (CNAMEs) are useful for pointing one host name at another.
MX	Mail exchange record	Maps a domain name to a list of mail transfer agents for that domain. MX records are those that are looked up by mail servers when email needs to be delivered.
NS	Name server record	A NS record tells recursive name servers which name servers are authoritative for a zone.  Recursive name servers look at the NS records to work out who to ask next when resolving a name.
PTR	Pointer record	While the A record points a domain name to an IP address, the PTR record resolves the IP address to a domain/hostname. PTR records are used for the reverse DNS (Domain Name System) lookup.
SOA	Start of authority record	Specifies authoritative information about a DNS zone, including the primary name server, the email of the domain administrator, the domain serial number, and several timers relating to refreshing the zone.
SRV	Service record	SRV record is a specification of data in the Domain Name System defining the location, i.e. the hostname and port number, of servers for specified services. The SRV records relate to a particular service of the domain, like FTP or SIP, rather than a specific machine the way A or C-name records do.

Lockdown mode

Lockdown mode on an ESXi host

When Disabled - We can use Windows vSphere client to manage the ESXi host even when it is added to the vCenter Server.
The changes we made through vSphere client in the ESXi host will be reflected in the vCenter Server or added to the vCenter database after the polling interval (which is about 5 minutes).

When Enabled - We can manage the ESXi host remotely, only through vCenter Server to which the ESXi host is added. We can not access it using Windows vSphere client.


Note - We can manage the ESXi host using DCUI (Direct Console User Interface) by physically accessing it even when it is set to Enabled.

80244019

Error Code 80244019

To resolve this problem, follow these steps: 

1. Stop Windows Update service 
2. Rename Software Distribution folder 
3. Start the Windows Update service. 
4. Try to install update. 

80070663

Error Code 80070663

If you are getting the error 80070663 while running Windows Update follow the below Microsoft Support links

https://support.microsoft.com/en-gb/kb/913754

http://microsoftlivesupport.com/blog/tag/80070663/

Advanced Disk Cleanup

Advanced Disk Cleanup Utility

Disk Cleanup Utility determines which files on a hard drive may no longer be needed and delete those files to free up disk space. Using Disk Cleanup on a regular basis improves system performance.

To access Disk Cleanup utility:

1. Click Start -> Run and in the Open box type cleanmgr and click OK (OR)

2. In Windows Explorer or My Computer, right-click the disk in which you want to free up space, click Properties, click the General tab, and then click Disk Cleanup.

Standard Disk Cleanup Options:

Advanced Disk Cleanup Options:

Advanced Disk Cleanup can delete temporary files on the system including debug dump files, system and user queued error reporting files, files discarded by Windows upgrade or setup and windows upgrade log files.

Open Command Prompt and type the below mentioned command:

%SystemRoot%\System32\Cmd.exe /c Cleanmgr /sageset:65535 & Cleanmgr /sagerun:65535

8007000E

Error Code 8007000E

If Windows Update failed to check for updates and displays error 8007000E

Download and install the patch KB3050265 (https://support.microsoft.com/en-us/kb/3050265)


Try running Check for updates again :)

VMware vCenter 6.0 Installation - Step by Step

Minimum hardware requirements for vCenter 6.0

1.  Run the vCenter Server installer

     2. Click on Next

3.  Accept license agreement and click next

4. Select deployment type and click Next

5. Choose System Network Name and click Next

6. Provide the Single Sign-On Configuration [If you are putting password, make sure your password meets the password complexity requirements]

     Password complexity requirements

    

     7.  Select the service account under which you want to run the vCenter Service

     8. Select your vCenter Database Configuration

     9. Configure the network ports to use [leave default if you don’t want to change any]

    10.  Choose the installation destination folder

Note: The vCenter Server with an embedded Platform services Controller installation requires about 18GB of free space on the installation drive.

    11.  Review settings and click on Install

     12. Below are few snapshots of installation progress

  

     13.  Click launch vSphere Web Client to start using it and hit finish the installation

    14. Access your new vCenter in the vSphere web client