Module 11 Configuring and Managing Distributed File System

Module Overview Distributed File System (DFS) Overview Configuring DFS Namespaces Configuring DFS Replication

Lesson 1: Distributed File System (DFS) Overview What Is the Distributed File System? How DFS Namespaces and DFS Replication Work DFS Scenarios Types of DFS Namespaces What Are Folders and Folder Targets? Namespace Server Requirements

What Is the Distributed File System? DFS technologies include: DFS Namespaces - provide a virtual view of shared folders located on different servers DFS Replication - provides high-availability and fault-tolerance to files and folders Remote Differential Compression - provides a compression technology that is optimized for data transfers over limited-bandwidth networks The Distributed File System incorporates technologies that provide fault-tolerant access to geographically dispersed files

How DFS Namespaces and DFS Replication Work User types: \\contoso.com\marketing Client computers contact a namespace server and receive a referral User types: \\contoso.com\marketing Client computers contact a namespace server and receive a referral 1 1 Client computers cache the referral and then contact the first server in the referral 2 2 Server in London User in New York DFS Replication Namespace \\Contoso.com\Marketing \\LON-SRV-01\ProjectDocs \\NYC-SRV-01\ProjectDocs User in London Server in New York Folder Targets

Types of DFS Namespaces CharacteristicDomain-basedStand-alone Path\\Domainname\Namespace\\Servername\Namespace Location Active Directory and memory cache Server registry and memory cache Size Up to 5,000 folders with targets in Windows® 2000 Server mode Up to 50,000 folders with targets in Windows Server® 2008 mode Up to 50,000 folders with targets Availability Namespace hosted on multiple servers Server cluster DFS ReplicationSupported

What Are Folders and Folder Targets? Folders: Are the primary elements of a namespace Have at least one folder target Folder targets include: Shared folders (\\server\share) Folders in a shared folder (\\server\share\folder) A path to another namespace (\\domainname\rootname) Namespace Server Folder Targets Namespace Root Folder Folders with Targets \\LDN-SRV-01\Tools London \\NYC-SRV-01\Tools New York \\NYC-SRV-02\Training New York \\Contoso\Public Software Tools Training Guides

Namespace Server Requirements A namespace server is: A domain controller or member server Windows Server 2003 or Windows Server 2008 Namespace server considerations: Must contain an NTFS volume to host the namespace Must be in the same domain if the namespace is domain-based Cannot be a clustered resource if the namespace is domain-based

Lesson 2: Configuring DFS Namespaces Deploying Namespaces for Publishing Content Security Requirements for Creating and Managing a Namespace Increasing Availability of a Namespace Options for Optimizing a Namespace

Deploying Namespaces for Publishing Content To configure a namespace for publishing content: Optional tasks: Create a namespace 1 1 Add folder targets 3 3 Create a folder in the namespace 2 2 Set target priority to override referral ordering 5 5 Set the ordering method for targets in referrals 4 4 Enable client failback 6 6 Replicate folder targets using DFS-R 7 7 You may also need to delegate the ability to create and manage namespaces

Increasing Availability of a Namespace Domain-based namespace: Specify additional namespace servers Stand-alone namespace: Create a stand-alone namespace as a cluster resource Folders: Specify additional folder targets Replicate folders using DFS Replication

Options for Optimizing a Namespace Methods for optimizing a namespace include: Rename or move a folder Disable referrals to a folder Referral cache duration Namespace polling

Lesson 3: Configuring DFS Replication What Is DFS Replication? What Are Replication Groups and Replicated Folders? DFS-R Requirements Scalability Considerations for DFS-R Process for Deploying a Multipurpose Replication Group Understanding the Initial Replication Process Generating Diagnostic Reports and Propagation Tests Troubleshooting DFS-R and Active Directory Troubleshooting DFS-R

What Is DFS Replication? Uses remote differential compression to efficiently update files over a limited-bandwidth network Detects changes on the volume by monitoring the USN journal Uses a staging folder to stage a file before sending and receiving it Uses a version vector exchange protocol to determine what files need to be synchronized Uses a conflict resolution heuristic of “last writer wins” for files that are in conflict and “earliest creator wins” for name conflicts Is self-healing and can automatically recover from failure Distributed File System Replication (DFS-R) is a multi-master replication engine that supports replication scheduling and bandwidth throttling

What Are Replication Groups and Replicated Folders? Member Projects Proposals Projects Proposals Replicated Folders Projects\Spec.doc Proposals\Budget.xls Connection Replication Group A set of servers, known as members, that participate in replicating one or more replicated folders Can be configured for multipurpose or data collection purposes Replicated Folder A folder that is kept synchronized on each member

DFS-R Requirements DFS-R Requirements include: The Active Directory schema must include the DFS replication objects Servers must be Microsoft® Windows Server 2003 R2 or Windows Server 2008, and must have the DFS-R service installed Servers in a replication group must be in the same forest Replicated folders must be stored on NTFS volumes On server clusters, replicated folders must be located in the node’s local storage Antivirus software must be compatible with DFS-R

Scalability Considerations for DFS-R Scalability considerations include: Each server can be a member of up to 256 replication groups Each replication group can contain up to 256 replicated folders Each server can have up to 256 connections The number of replication groups multiplied by the number of replicated folders multiplied by the number of simultaneously active connections must be kept to 1024 or fewer A replication group can contain up to 256 members A volume can contain up to 8 million replicated files, and a server can contain up to 1 terabyte of replicated files The maximum tested file size is 64 gigabytes

Process for Deploying a Multipurpose Replication Group Select the type of replication group to create 1 1 Add the replication group members 3 3 Specify the name and domain 2 2 Specify the replication group schedule and bandwidth 5 5 Specify a topology 4 4 Specify the primary member 6 6 Specify the folders to replicate and the local path on member servers 7 7

Understanding the Initial Replication Process Replication of DFS-R settings 1 1 Files are moved to DfsrPrivate\PreExisting 3 3 The primary member starts replication 2 2 Primary member designation is removed 5 5 Files are compared and replicated 4 4

Generating Diagnostic Reports and Propagation Tests Use the Diagnostic Report Wizard to: Create a health report Start a propagation test Create a propagation report

Troubleshooting DFS-R and Active Directory Error: Waiting for the DFS-R service to retrieve replication settings from Active Directory Possible Issues: Active Directory replication latency Active Directory replication blocked due to network mis-configurations Active Directory replication blocked due to topology mis-configurations Active Directory blocked due to lingering objects Active Directory replication blocked due to tombstone lifetime

Troubleshooting DFS-R IssuePossible CausePossible Solution DFS-R is slow Operating System not up to date Install latest updates and hotfixes DFS-R is slow Staging directory is too small (event 4208) Increase staging quota DFS-R is slow Large amounts of sharing violations (events 4302 and 4304) Examine how files are being used Data isn’t being replicated DFS-R might not work across firewalls when replicating between branch offices without a virtual private network (VPN) connection Define a static port using dfsrdiag.exe command-line tool Data isn’t being replicated DFS-R has a disconnected topology Repair the topology in DFS Management DFS-R not replicating.bak files DFS-R doesn’t replicate files starting with ~ or files with extension *.tmp or *.bak You can include these files in replication in DFS Management