Hi,Can anyone tell me what is the difference between DC,ADC and member server and in this case how do i find out what a specific server is i mean how do i come to know that the server is DC,ADC or member server

In an Active Directory environment you can have Domain Controllers. (DCs) These servers are equiped with the Active Directory Domain Services role and the Active Directory Domain Services management tools.Admins of these servershave run dcpromo to promote the server to a Domain Controller.Domain Controllers host the Active Directory Domain Servers database, allow connections to this database, take care of replication and host the SYSVOL and NETLOGON shares. People tend to think in terms of the first Domain Controller and additional Domain Controllers (ADCs), but in fact there might not be a difference between these Domain Controllers. The first Domain Controller by default is a Global Catalog (GC) and holds all five FSMO roles. You can make ADCs Global Catalogs as well and you can transfer FSMO roles between Domain Controllers. Member servers are domain joined Windows servers. The main difference between Domain Controllers and member servers is the place where authentication takes place. A Domain Controller authenticates against the Active Directory database (unless running in DSRM), where a member server can authenticate against both the Active Directory database and the local account database. Member servers do not host any Active Directory Domain services. And then there are workgroup-joined computers. These are non-Active Directory Domain joined servers. This is the default state of a Windows Server (after installation from non-customized installation media).You can easily spot Domain Controllers using thewmic.exe ComputerSystem get DomainRole command described in the following link: How to tell whether its a Domain Controller

Thanks for you answer so as per your explanation the first DC holds the GC andFSMO roles so if i move the GC andFSMO roles to the ADC then the ADC will become DC ,i guess i am not wrong

No. thats not the case. ADC is always a DC. even if the DC is not a GC and is not holding any FSMO roles , it is still a DC. Yes, you can have DC as GC and you can distrubute the FSMO roles to multiple DC's and GC's.Raj

Thankx for your answers guys so now i think am close to my answer which i am looking for, So if i am running an DC with active directory and if ihave one member server which is not the DC but its just added in the domain so can i host exchnage in the member server or is it necessary the server hosting Exchnage should be a DC or ADC ????

Your member sever can host the Exchange application. It is actually best practice not to put Exchange on a DC unless its for a lab or test environment. Exchange installed on a DC is not supported by Microsoft in production.Mark Morowczynski|MCT| MCSE 2003:Messaging, Security|MCITP:ES, SA,EA|MCTS:Windows Mobile Admin|Security+|http://almostdailytech.com

can i host exchnage in the member server or is it necessary the server hosting Exchnage should be a DC or ADC ???? One of the requirements of Microsoft Exchange server (since Exchange 2000) is Active Directory.You can install Microsoft Exchange server on a Domain Controller (DC) or on the member server, BUT installing Microsoft Exchange Server on a Domain Controller is not supported, or a best practice, for a couple of reasons: When Microsoft Exchange is installed on a Domain Controller, the Microsoft Exchange installation will only communicate with the locally available Active Directory database. When the Active Directory database on the Microsoft Exchange Server breaks, your Exchange installation breaks. When you install Microsoft Exchange Server on a member server in an environment with multiple Domain Controllers, one of the Domain Controllers can break, without it causing Exchange outage. Microsoft Exchange offers services, that are appealing to publish on the Internet. For instance, Outlook Web Access (or Outlook Web App, as it is called in Exchange Server 2010) can be used in fallback scenarios (when a colleagues Outlook installation fails) but is much more useful when you use it to allow your colleagues to access their mail outside company hours and outside company walls. When Exchange is installed on a Domain Controller, you put your Active Directory information at unnecessary risk. When a server is promoted to Domain Controller, write-back caching is disabled. This impacts storage performance negatively by about 30%. This is done for data consistency reasons. Microsoft Exchange Server is a very disk intensive application, that will suffer dramatically when you install it on a Domain Controller. My advice:Install Exchange Server on a member server. If you need redundancy in your Active Directory environment, implement a third server and make it an additional Domain Controller (ADC). Be sure to make it a Global Catalog as well (and reboot afterwards), since Microsoft Exchange only communicates with Domain Controllers that are Global Catalogs.

Wonderful answer now i come very close to my production environment problem which i am facing,This is my currentr setup and problem DC1: Which holds all the FSMO roles (Main DC) (OS - windows server 2003)DC2: Additional domain controller with Exchnage Server (OS - windows server 2003 Exchange server 2003)DC3: Front end server(OS - windows server 2003 Exchange server 2003)Now we have found that DC1 and DC2 are not replicating infact even the netlogon folder is missing from DC2 and it has crossed the tombstone ,recently i created a new storage group in exchnage server which i found missing in the main DC iee DC1 and Front End server iee DC3,but at the same time when i create a new user or make any chnages in DC1 it gets reflected in DC2,So i am planning to make the exchange server as member server but now again a question arises if i directly remove my exchange server as DC and make it as member server will my exchange server users will be effected while accessing mails or there are any additional steps to do this process,because i feel that after making the Exchnage server as member server i won't face replication problem .since it will be only a member server not an DCSo that DC3 which is front end server can i make this as ADC

Abu, as i have suggested you earlier. exchange should never be on a DC but should be a member server. Even the front end should not be a DC (as even that is an exchange server). so as suggested earlier get a new server and promote that as a DC. The real challenge here will be to run a dcpromo to demote a live exchange server.Raj

Rajnish ,Backend server hosts all the mailboxes so there would be lots of load on the Exchnage Server to make it DC agreed,But front end server dosen't hosts mailboxes so why can't we make it ADC,im not sure??Sois the mailboxes or any other services which microsoft recomends not to make any Exchnage server as DC in simple words what is the load which runs on Exchange Application that we don't make it as DC no matter its Frontend or Backend.Why do microsoft prefers to make it Member server instead of DC.