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Showing posts from July, 2015

Active Directory and Active Directory Domain Services Port Requirements

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The following table lists the port requirements for establishing DC to DC communication in all versions of Windows Sever beginning with Windows Server 2003 Protocol and Port AD and AD DS Usage Type of traffic TCP and UDP 389 Directory, Replication, User and Computer Authentication, Group Policy, Trusts LDAP TCP 636 Directory, Replication, User and Computer Authentication, Group Policy, Trusts LDAP SSL TCP 3268 Directory, Replication, User and Computer Authentication, Group Policy, Trusts LDAP GC TCP 3269 Directory, Replication, User and Computer Authentication, Group Policy, Trusts LDAP GC SSL TCP and UDP 88 User and Computer Authentication, Forest Level Trusts Kerberos TCP and UDP 53 User and Computer Authentication, Name Resolution, Trusts DNS TCP and UDP 445 Replicatio

Linux and Unix: L1 & L2: System Administration Interview Questions

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1)  What is GRUB GNU GRUB is a Multiboot boot loader. It was derived from GRUB, the GRand Unified Bootloader, which was originally designed and implemented by Erich Stefan Boleyn. Briefly, a boot loader is the first software program that runs when a computer starts. It is responsible for loading and transferring control to the operating system kernel software (such as the Hurd or Linux). The kernel, in turn, initializes the rest of the operating system (e.g. GNU) 2) Explain Linux Boot Process Press the power button on your system, and after few moments you see the Linux login prompt. Have you ever wondered what happens behind the scenes from the time you press the power button until the Linux login prompt appears? The following are the 6 high level stages of a typical Linux boot process.

Advance VMware HA interview Q & A

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Q1: Exp l a i n h o w re s t a rt of V M ’s i s h a n d l ed b y HA i n case o f a ma s ter E s xi Host f a il u re. An s : H A r e star t s VM’s a ft e r f ai lu re of a n E s x i ho s t . B u t t he t i me t a k e n by H A to re s t a rt VM’s i s di ff e r e nt i n c a s e of a s l a ve E s x i fa i lu re a nd m a ster E s x i fa i lu r e . W e will di s c u ss h e re t he ca s e wh e n ma ster E sxi ha s f ai l ed . In ca s e of a f ai lu re of a m a ster E s xi , r e start of V M ’s a re de l a y e d t i l l t he t i me a n e w m a ster i s e l ec t e d b e c a u se only a m a ster c a n p e r f orm VM r e star t . The t i m e l i ne i s ex pl ai n e d a s f o ll o w s: ·      T0 – M a ster f ai lu r e . ·      T1 0 s – M a ster e l ec t i on pro ce ss i n i t ia te d . ·      T2 5 s – New m a ster e le c t e d a n d r e ad s t he pro t ec t e d list. ·     T35s – New m a s

Microsoft: What is Blue Screen of Death (BSOD)

Blue Screen of Death If you have been working on computers or are just starting to use them, one of the most disturbing events that can occur is the BSOD or Blue Screen of Death. The BSOD is actually an error screen that is displayed by specific operating systems informing the user that a critical system error has occurred. The Blue Screen of Death can be found on many different types of operating systems, but is most notably infamous for occurring on Microsoft Windows Operating Systems. Common Causes of the Blue Screen of Death Occurring\ Not Cause 1. It doesn’t occur because of operating system Cause 1. Including a poorly written device driver 2. Faulty memory 3. Incompatible DLL’s or a corrupt Registry. (3rd party software) Poorly written device driver:  A device driver is usually created by a third party company to run a device such as a peripheral (printer, scanner, mouse, etc). These third party companies’ create small driver programs which make it possible for these devices t

Microsoft: SID issue while cloning the Windows VM's

Procedure to clone VM's and avoid SID issue Step 1:  Take the backup or image copy if the source machine. Step 2 : convert the source machine from domain to workgroup                ( Note : 1. Before convert into workgroup just take the information of SID’s                             2. After convert into workgroup try to find the SID’s ) Step 3:  proceed with clone request Step 4:  Once the clone VM got deployed.                 Task 1: Update the IP Details and change the hostname to new hostname                 Task 2: Reboot the machine                 Task 3: join the machine to domain                 Task 4: Reboot the machine Step 5:  Check the SID’s and you find the  different. Command’s: psgetsid  “host name”  – for local server psgetsid  “system”  – for local system psgetsid  “administrator”  – it will show SID details when it got connected to domain psgetsid  “hostname$”  - – it will show SID details when it got connected to domain

Tips & Tricks: Microsoft Clustering Resources useful Guide

Microsoft Clustering Resources This has to be the mother of all resource collections on Microsoft clustering and high availability.  I’ve copied over the links  directly from the MS Cluster blog so that I have quick access to them in the future. General Resources ·          Cluster Team Site:  Clustering Technical Resources ·          Guide:  Failover Clustering Deployment ·          Guide:  Validating Hardware for a Failover Cluster ·          Guide:  Migrating Cluster Settings ·          Guide:  Configuring the Quorum in a Failover Cluster ·          Guide:  Configuring Accounts in Active Directory ·          Guide:  Configure a Service or Application for High Availability ·          Guide:  Modifying Settings for a Failover Cluster ·          Guide:  Installing a Failover Cluster ·          Guide:  Creating a Failover Cluster ·          Guide:  Cluster Requirements ·          Guide:  Validating a cluster ·          Guide:  Managing a Failover Cl

Microsoft iSCSI Software Target 3.2: Known Issues and Updates

Do not rename resources outside of the Microsoft iSCSI Software Target console . If you rename an iSCSI resource after it is created, unexpected results may occur. If a resource is renamed with another tool, such as Failover Cluster Management, different naming rules may apply that may lead to issues for Microsoft iSCSI Software Target. For example, Failover Cluster Management permits a resource name to contain a space, whereas Microsoft iSCSI Software Target does not. If an iSCSI resource has been renamed, delete the resource, stop the Microsoft iSCSI Software Target service, and then restart the service and recreate the resource. Increase iSCSI initiator timeout value when you use Failover Clustering.  If you enable IPSec on connections from iSCSI initiators to a failover cluster running Microsoft iSCSI Software Target, you should increase the iSCSI initiator timeout value. Increasing the timeout value will prevent communication failures when a failover node goes offline and the o

Part - 3: Exchange Interview Question & Answer

EXCHANGE SERVER DS PROXY DSProxy is the component in Microsoft Exchange Server 2003 that provides an address book service to Microsoft Outlook clients. Although the name implies that this component provides only proxy services, DSProxy provides both of the following services: 1. DSProxy emulates a MAPI address book service and sends proxy requests to an Active Directory server. 2. DSProxy refers Outlook client queries to an Active Directory server. DSAccess The Exchange components that need to interact with Active Directory use DSAccess to retrieve Active Directory information rather than communicating directly with domain controllers and global catalog servers