Tuesday, October 28, 2014

Top 5 Daily SharePoint Disasters - White Paper

Metalogix has published an interesting White paper that talks about the Top 5 Daily SharePoint Disasters that SharePoint Administrators have to deal with almost on a daily basis while supporting Small or Medium or Large scale Enterprise Wide SharePoint Farms.

Here is the top 5 Daily Disasters that occur in a SharePoint farm and their recovery strategies:

1. Restoring Missing Documents:
Administrators are frequently tasked with addressing user requests to restore missing SharePoint content. While the introduction of Recycle Bin in SharePoint 2007 went a long way to reduce these requests, they still occur.

Oftentimes, a user can retrieve documents without the assistance of an administrator, if they act quickly. However, SharePoint’s Recycle Bins do not hold their contents forever. Most environments are configured to automatically flush their Recycle Bins for reasons of content size (i.e., too much in a bin) and age (i.e., a document is too old).

Documents can also disappear as a result of workflow and information management policies (such as retention policies). These may move documents between sites and site collections without a user’s knowledge. In some cases, these same mechanisms may delete documents entirely.

Multiple deletions from a document library is another problem. In these cases a user may not know which documents were deleted – only that they need to restore everything that went missing after at a particular time

Follow these steps to mitigate the “disappearing document” problem:
> Ensure that both first and second stages of the SharePoint Recycle Bin are enabled. Ideally, an item-level backup and restore strategy should be implemented to ensure that documents can be recovered in the event that they “disappear.”

> If you’re charged with restoring a document and the above stages weren’t yet enabled, you’ll need to identify compositional differences between the past and present states of the target document library. This is a less than ideal solution, for anything but the smallest of document libraries, this process can be extremely tedious and time consuming at best with conventional SharePoint administrative tools.

2. Restoring from Previous versions of Documents:
Document version recovery is a complex process and critical to users. Be sure to adopt a layered approach to ensure document version restores are simplified.

> Turn on versioning within document libraries.
> Enforce a document check-in/check-out to ensure only one user is working on a document at any given time.

Restoring documents that don’t exist in the form that matches user expectations is another common problem.

This often occurs when versioning for the list or library isn’t enabled – eachtime a user saves a document back to SharePoint, that document overwrites its previous version. However, versioning isn’t a fix-all solution. If you’re storage-conscious and limit the number of document versions that can be retained – then a complete document history may not be available. In fact, once the number of check-ins permissible by the version retention policy is reached for a given document, SharePoint deletes older versions of that document to accommodate newer versions.

Documents deleted as a result of retention limits do not go to the SharePoint Recycle Bin – they are permanently gone.

3. Corruption in a Content Database:
Content database corruption is problematic because it affects all users working with the site collections in that database. A SharePoint content database can house hundreds or even thousands of site collections. Having a content database fall out of circulation has the potential to affect most, if not all, users in a SharePoint environment.
Once a SharePoint environment is in-use, most administrators just create site collections as they are needed without giving much thought as to where those site collections go. Additional databases only get created as they are needed – typically when the “current” content database is reaching Microsoft’s maximum size (which varies from 200 GB to quite a bit larger depending on the performance of the underlying SQL Server).
Out-of-the-box high availability (HA) mechanisms generally do little to help with corrupted content databases. Some HA mechanisms, such as SQL Server’s mirroring and AlwaysOn Availability Groups, have the ability to repair inconsistencies that occur during mirroring or replication. If the source of content database corruption is external to the mirroring or replication mechanism, though, then HA simply guarantees “highly available corruption” – not a way to repair SharePoint content.
Corrupted Content Databases are a tricky problem with very few practical fixes.

> Perform regular content database backups.
> As with all backup regimens, test frequently to ensure that you can restore as desired!

4. Deleted Site Collection:
It’s quite common for users to unintentionally delete SharePoint site collections or sub-sites.
Microsoft recognized the prevalence of this problem during the SharePoint 2010 timeframe and introduced the Site Recycle Bin as part of Service Pack 1. The Site Recycle Bin extended standard Recycle Bin support to include site collections and sub-sites that were deleted. Now, although end users can restore deleted sub-sites by themselves from within the SharePoint web user interface, you’ll still need to perform an administrative action to restore an entire site collection using the Site Recycle Bin.

This is due to the fact that site collections can’t be restored from within the web user interface or even Central Administration. Instead, restoring a site collection for the Site Recycle Bin has to be done with PowerShell (specifically, the Get- SPDeletedSite and Restore-SPDeletedSite cmdlets) on your SharePoint member server.

To prevent and mitigate the problem of deleted site collections:
> Ensure that SharePoint’s Recycle Bins are configured and enabled to catch deleted site collections.
> Implement a solid backup and restore strategy for site collections and/or their associated databases.

5. Deleted Permissions settings:
The deletion of unique permissions applied to SharePoint lists or libraries by absent-minded users is a tricky one to reverse, since SharePoint’s built-in data protection toolset offers no options for restoring permissions.
The only option is to either manually re-apply all of the custom permissions to items in the list, or delete the list and attempt to import a known “good copy” that was exported from a backup set. Previously executed tests will provide much needed confidence in any restore action. The former choice is especially time consuming, while the latter results in the loss of content modifications since the last backup. Either case is far from ideal because a compromise must be made.

Without the right out-of-the-box tools in place, a site collection (or content database) backup/restore is needed.

Monday, October 27, 2014

Best Practices for ASP.NET MVC

There is a nice write-up on the MSDN Blog site dedicated to Best Practices for ASP.NET Model-View-Controller pattern.

Read the full article at MSDN Blog: http://blogs.msdn.com/b/aspnetue/archive/2010/09/17/second_2d00_post.aspx

Wednesday, October 15, 2014

Optimize SharePoint Performance

Eric Shupps, a renowned Microsoft MVP has written an excellent White Paper published by Metalogix for optimizing SharePoint performance. I found the tips valuable and agree with Eric's suggestions as I have personally found incorporating a lot of them extremely helpful in improving SharePoint performance.

A common misconception is that servers connected to a high-speed network segment (such as gigabit Ethernet or Fiber) will have plenty of bandwidth to perform all required operations. While it is unlikely that a high-speed link will ever be fully saturated at any given moment, it is quite possible that physical resource contention may have a direct impact on the performance of a specific operation. SharePoint places a tremendous amount of demand on SQL—each request for a page can result in numerous calls to the database, not to mention the additional overhead required by service jobs, search indexing, and other operations.
In order to mitigate the conflict between user and database traffic, connectivity between front-end servers and SQL should be isolated, either via separate physical networks or virtual LAN’s. Typically, this requires at least two separate network interface cards in each front end web server with static routes configured to insure traffic is routed to the correct interface. The same configuration may also be applied to application and index server, although the perceived benefits will be less as these server roles typically do not involve much direct user traffic (environments which utilize InfoPath Forms Services and Excel Services will benefit the most).
The following is an example of a typical configuration optimized for data connectivity. In this scenario, Servers A functions as a Web Front End, while B performs index operations, C is an Active Directory domain controller and D hosts the SQL database:

An important issue that must be taken into account when considering the separation of WFE/Index servers and the SQL database is the use of firewalls. Network security policies often dictate the isolation of database servers behind a firewall which restricts communication to only a handful of necessary ports. Caution should be taken in this type of configuration to insure that the firewall ports operate at sufficient speed to insure optimal data transfer and that only the minimal amount of required filtering and packet analysis are being performed. SharePoint applications are very data intensive and the database connection can often be the most significant bottleneck; whenever this connection is impeded by a firewall, thorough load and scalability testing should be performed to assess the impact on portal operations under heavy use.
A typical medium server farm consists of one or more web front end servers, a dedicated index or application server and a separate SQL database server. In this scenario, search traffic initiated by the index server must be processed by the same servers responsible for delivering end-user content. The crawl process can create a tremendous amount of network traffic as the Search service must make a number of HTTP requests for each page in the hierarchy. Failure to isolate this traffic can have a negative impact on performance as search requests conflict with user traffic competing for the same limited amount of physical bandwidth.
In order to prevent search and user traffic from conflicting with each other, an additional server may be added to the farm which is dedicated solely to servicing search queries (alternatively, in smaller environments, the index server may also serve this function). The farm administrator would then configure the Search service to perform crawls only against this dedicated server, thereby eliminating excessive load on the web front end servers during index operations and reducing the amount of potentially conflicting requests. Depending upon the scope and frequency of search crawls, this configuration can reduce traffic to the web front end servers by as much as 70% during index operations.
SQL performance tuning is a discipline unto itself but there are some simple things that SharePoint farm administrators can do to improve performance without requiring the services of an experienced DBA. To begin with, the implementation of SQL should be planned at least as carefully as the SharePoint farm itself; perhaps more, considering the level of detail that can be involved. Physical hardware resources, network connectivity, disk size and speed, location of data files, configuration of shared storage—all aspects must be taken into consideration based on the size of the farm and the projected amount of data.
One quick way to avoid future headaches is to provision the major SharePoint databases onto separate physical disks (or LUNs if a SAN is involved). This means one set of disks for search databases, one for temporary databases, and still another for content databases (depending upon the size of the individual content databases these may require further separation). SharePoint is both read and write intensive, so separating the I/O operations onto separate disks prevents excessive thrashing and cache hits. Additional consideration should be given to isolating the log files (*.ldf); although these do not incur the same level of I/O as other files, they do play a primary role in backup and recovery and, because they can grow to several times the size of the master database files, can consume a great deal of disk space.
Another simple optimization technique is to proactively manage the size and growth of individual databases. By default, SQL grows database files in small increments, either 1MB at a time or as a fixed percentage of database size (usually 10%). These settings can cause SQL to waste cycles constantly expanding databases, especially in larger environments which utilize a great deal of storage space, and prevents further data from being written while the databases are expanding. An alternative approach is to first pre-size the databases up to the maximum recommended size (100GB) if space is available and set autogrowth to a fixed size (e.g. 10MB or 20MB). This will prevent SQL from expanding databases unnecessarily and insure that growth happens in a manageable fashion.
Finally, autogrowth, and its corollary, autoshrink, are prone to producing excessive fragmentation, especially when done in small increments. Even on fast disks fragmentation can have a substantially negative impact on performance, a situation which may be compounded by complex RAID configurations and distributed SAN storage. Disk defragmentation should be scheduled on a frequent basis to insure that SQL is using resources effectively.
SQL Server maintains its own set of indexes for data stored in various databases in order to improve query efficiency and read operations. Just as with files stored on disk, these indexes can become fragmented over time as new INSERT, DELETE and UPDATE operations are performed. This can have a particular effect on SharePoint as many of the behind-the-scenes query operations are not optimized for large datasets (such as list views encompassing hundreds of thousands of items).
Index fragmentation is a complex topic best left to SQL DBA’s but it is important for administrators to plan for regular maintenance operations which include index defragmentation. Special care should be taken to schedule these types of operations in a maintenance window as they are both resource-intensive and, in many cases, blocking tasks which prevent data from being written to or read from the indexes as they are being rebuilt. Service Pack 2 for SharePoint Server 2007 and WSS v3.0 contains updates to the database index management routines functionality and scheduling but enterprise administrators who manage large farms may wish to implement their own index defragmentation maintenance tasks and schedules.
Most SharePoint data is stored in lists: Tasks, Announcements, Document Libraries, Issues, Picture Libraries, and so forth. A great deal of this data is actually stored in a single table in the content database associated with the site collection. Regardless of how many sites and subsites are created within the SharePoint hierarchy, each Site Collection has only one associated Content Database. This means that a Site Collection with thousands of subsites is storing the bulk of the user data from every list in every site in a single table in SQL.
This can lead to a delay in the time it takes to insert items, render views, and navigate folders in any given list, as SQL must recursively execute the various queries over one potentially very large dataset. One way to reduce the workload is to manage the mapping of site collections to content databases. Administrators can use the Central Administration interface to pre-stage content databases to insure that site collections are associated with a single database or grouped logically based on size or priority. By adjusting the Maximum Number of Sites setting or changing database status to ‘offline’, administrations can also control which content database is used when new site collections are created.
The SharePoint user interface is intended to make it easy for information workers to manage content and find resources. For users connected to the portal over the corporate LAN this doesn’t pose much of a problem but for disconnected users on slower WAN links or public facing websites the heavyweight nature of the typical SharePoint page can prove to be a real performance-killer. Fortunately, there are a number of ways to reduce the bloat and trim those pages down to a more manageable size.
First, when designing a new look and feel, it is helpful to start with a minimal master page. The master page contains all the chrome and navigation elements typically found on the top and left of a standard SharePoint page—things like the search box, global navigation, Quick Launch, Site Actions menu and other visual element. A minimal master page, as the name implies, removes unnecessary elements and allows designers to start with a clean slate that only contains the base functionality required for the page to render correctly.
Second, most SharePoint pages contain links to supporting files, including javascript and style sheets, which require additional time to retrieve and execute. Designers can alter the way in which SharePoint pages retrieve these files through a technique called “delayed loading”, which essentially loads the linked files in the background while the rest of the page is rendering, allowing users to view content without waiting for all the back-end processing to take place.
Finally, there are programmatic ways to reduce page sizes in SharePoint which developers can implement relatively easily. One technique is the elimination of whitespace—dead weight which makes the page more readable to developers and designers but which has no impact on the ability of a client browser to render the page. Another method is to remove specific javascript and authoring content entirely based upon a user’s permission level. Developers may also wish to disable ViewState persistence for specific page objects and implement custom server controls which leverage caching mechanisms that are more efficient than the default cache objects in SharePoint.
SharePoint content consists of two primary sources—static files resident in the SharePoint root directories (C:\Program Files\Common Files\Microsoft Shared\12 for 2007 and \14 for 2010) and dynamic data stored in the content database (web parts, publishing field controls, navigation controls, etc.). At runtime, SharePoint merges the page contents from both sources prior to transmitting them inside an HTTP response to the requesting user. Internet Information Server versions 6 (Windows Server 2003) and 7 (Windows Server 2008) both contain various mechanisms for reducing the payload of HTTP responses prior to transmitting them across the network. Adjusting these settings can reduce the size of the data transmitted to the client, resulting in shorter load times and faster page rendering. It is important to note that doing so can have an impact on CPU load and memory utilization – care should be taken to insure that sufficient hardware resources exist before tuning IIS compression settings.
IIS compression settings can be modified from a base value of 0 (no compression) to a maximum value of 10 (full compression). Adjusting this setting determines how aggressive IIS should be in executing the compression algorithms. Setting the value to 4 can result in a static linked file such as core.js being reduced in size from 79k
to 60k, resulting in a payload reduction of 24%. Turning it up to 9 will reduce the size even further to 57k (it is generally recommended to avoid using the max setting of 10 as this can place excessive demands on the CPU). Environments which employ extensive custom branding and customization, and those with a large proportion of remote users on slower connections, will benefit the most from adjusting IIS compression levels.
SharePoint serves up a lot of data but not all of it is retrieved in real-time from the database. Much of the content requested by users can be cached in memory, including list items, documents, query results and web parts. How, when and by what rules SharePoint caches content is governed by cache profiles which can be configured for a single site or an entire site collection. Each cache profile is comprised of settings which tell the system which content to cache, who to cache it for, when to release it and when to check for updated content.
Site administrators can configure their own cache profiles to meet different user needs. Anonymous users, for example, can be assigned one set of cache policies while authenticated users are assigned another, allowing content editors to get a more recent view of content changes than general readers. Cache profiles can also be configured by page type, so publishing pages and layout pages behave differently, and administrators have the option to specify caching on the server, the client, or both.
In addition, the SharePoint Object Cache can significantly improve the execution time for resource-intensive components (such as the Content Query Web Part). By determining in advance whether or not to check for new query results on each request or to use a set of previous results stored in memory, queries which cross site boundaries can be prevented from making excess demands on the database. Large objects which are requested frequently, such as images and files, can also be cached on disk for each web application to improve page delivery times.
SharePoint Designer is a useful tool for administrators and power users but it has a side-effect which can be harmful to overall performance: page customizations (or, in legacy parlance, ‘unghosting’). A customized page is one that has been opened in Designer, modified and saved. This has the effect of breaking the coupling between the pages on disk in the SharePoint Root folders and data in the content database. When customization occurs, the entire page content, including the markup and inline code, is stored in the database and must be retrieved each time the page is requested. In most cases, this introduces relatively little additional overhead on a page-by-page basis, but in larger environments with hundreds or even thousands of pages, all that back-and-forth to the database can add up to significant performance degradation.
To prevent this problem, administrators should implement a policy which restricts page customizations to only those situations where it is absolutely necessary. It may be fine, for example, for select contributors to customize user-authored layout pages in the /pages system library, while master and default layout pages are strictly off-limits. Also, it may be necessary to set up a ‘sandbox’ environment where users can create custom web parts which can then be imported into production without having to open controlled pages directly in SharePoint Designer. Site Collection and Farm administrators also have the option of completely disabling the use of Designer or, when necessary, using the “Reset to Site Definition” option to undo changes and revert back to the original content.

One of the most significant design elements on any portal site is the global, drop-down, flyout menu at the top of each page. It seems like a handy way to navigate through all the various sites and pages—until it becomes so deep and cluttered that all ability to navigate beyond the first few levels is lost completely. Even worse, fetching all the data to populate the navigation menus can be resource-intensive on sites with deep hierarchies.
SharePoint designers have the ability to customize the depth and level of each navigation menu by modifying the parameters for the various navigation controls within the master page. When using dynamic navigation, SharePoint builds a site hierarchy in the background and caches this information, helping to reduce the amount of data retrieved from the database, and stores it in an XML file. The size of this file, cached or otherwise, can impact the ability of pages to render in a timely manner—the controls must still be populated with all of the nodes in the hierarchy.
Administrators should limit the depth of navigation to a manageable level which is both usable and constrained to a number of sites that does not impact performance. Furthermore, if the Pages library contains a large number of documents and the Pages option is selected in navigation settings, rendering the current navigation elements can also have a negative impact on performance; either exclude Pages from navigation or limit the amount of documents in this system library.
SharePoint offers a tremendous array of options for improving performance and efficiency of collaborative portal applications. Understanding the inner workings of the framework and its dependencies upon key infrastructure components, including servers, network connections, services, operating system components and databases, is vital to the success of any optimization strategy. Implementing basic performance enhancements as outlined in this paper can provide tremendous improvements to the operation and performance of SharePoint within the enterprise.