Thursday 20 August 2015

Non Functional Testing for SharePoint

Overview:  Functional Requirements are the business requirements that the business define for the application being built.  Non-functional testing is concerned with performance, reliability, scalability, recovery, load,  security and usability testing.  For SharePoint it is a good idea to test this at a platform level and then verify the individual application non functional testing is appropriate.

SharePoint Non Functional Testing:
All of these test should be performed against your various SharePoint platforms and will dictate the SLA's offered to the business using SharePoint as a service.  Baseline testing is a good idea as the differences can be used to determine the efficiency of the individual application being created.

Proxies:
Fiddler is my favourite (other tools for capturing web traffic Charles, BurpSuite, WireShark and you can use the developer tools shipped with the browsers). tcpdump, goPacket are awesome for network monitoring.

Use Fiddler to:
  • Observe traffic (http/https requests, headers,..)
  • Replay sessions, 
  • Evaluate performance,
  • Set break point
A common misconception is the function of performance vs load testing.  

Performance is primarily concerns with looking at typical user usage scenarios and see how long each page takes to load.  So a recorded script with wait time between recorded calls is useful  It's also worth looking at the same page with minimal data and also with large amounts of data.  

Load Test involves recording the standard users interaction (ensure some users query heavy and some light amounts of data), there are no wait times.  The norm is to multiple this concurrent number of users by 100 to know the amount of users the farm business application can support.  e.g. a concurrent user load of 100 users where the performance is acceptable means the farm should handle 10,000 users (100 users times 100).  You run the 100 users in a steady state for a few hours.

Stress testing is similar to load testing but you keep stepping up the number of concurrent users until the SharePoint farm starts running out of resources and throttling requests.  Once the system degrades and performance is not acceptable is pretty much how many users the application on the SharePoint farm are supported.  So if the performance throttles at 170 users, the farm can handle 17, 000 normal usage users.

References:
http://www.guru99.com/non-functional-testing.html

Sunday 16 August 2015

FedAuth Notes for Problem Solving

Overview:  These are my notes on FedAuth relating to SharePoint 2013.
SharePoint (SP) 2013 uses Claim Based Authentication (CBA).  In this example, I am looking at SiteMinder (a CA product) as the Federation Service (this is the equivalent to ADFS (Active Directory Federation Service) as the Identity Provider (IdP)).
Basic Flow of SP CBA Authentication:
  1. SP looks for a FedAuth cookie; if  there is no FedAuth cookie for the users, it shall redirect the user to login via the IdP (AAD/SiteMinder/ADFS et al.). 
  2. The IdP returns a valid SAML token to SharePoint's STS.
  3. The STS generated a FEDAUTH cookie for the user to hold the current users session lifespan state (to keep the user log in).  The user holds the STS token not the SAML token.  The FedAuth in is a pointer to the SAML token held in the SharePoint Token Cache.
The default behaviour of SharePoint is to store the FEDAUTH cookie on the user’s disk, with a fixed expiration date. The expiration of the FEDAUTH cooking can be for a fixed time or a sliding session (if the user interacts with SP, the SP session is extended).  FedAuth can be stored on the Disk (default or in memory (not persisted between browser close downs). 

Note:  Changing where the cookie is stored affects the way the user shall login and effects Office application login such as Word.  Test thoroughly before changing)

Note:  Watch the IdP providers expiration policy vs what you set up in SP.  As an example, you could remove a user from the IdP, however, the session is still persisted and the user can still interact with SharePoint.   From MSDN "Make sure that the value of the LogonTokenCacheExpirationWindow property is always less than the SAML token lifetime; otherwise, you'll see a loop whenever a user tries to access your SharePoint web application and keeps being redirected back to the token issuer." 

Note: Closing a browser window with the FEDAuth stored to Disk does not invalidate the SharePoint session.  So the FedAuth shall persist when IE is close.  However, by keeping the session lifespan/FedAuth lifetime relatively short, the  to be relatively short (think less than an hour) your security is better.
Note: Change from FedAuth to session based sessions should taken lightly, Office products need to be thoroughly tested and generally won't work seamlessly.

Updated 11 Feb 2019: rtFA cookie
"The root Federation Authentication (rtFA) cookie is used across all of SharePoint Online and the rtFA cookie is used to authenticate the user silently without a prompt.  So when moving from OneDrive to SPO or Admin sites, the user does not get additional prompts for login.  When a user signs out of SharePoint Online, the rtFA cookie is deleted."

References:
SharePoint Authentication and Session Management
https://msdn.microsoft.com/en-us/library/hh446526.aspx
Remote Authentication for SharePoint Online (RTFA)
Why IE and Office work together in SP
Adding, removing SP claims and managing security using claims  and NB! also
Logout of SharePoint
 NB!  http://blog.robgarrett.com/2013/05/06/sharepoint-authentication-and-session-management/
Check Cookie TimeOut; set by formula:
FedAuth LifeTime = IdP endpoint SAML token lifetime Duration - STS LogonTokenCacheExpirationWindow

Update 04 Feb 2016: screenshot for clarity:


My blog post on changing from FedAuth to session based cookies.  The post also shows how to examine the cookies for Internet Explorer (IE).

Sunday 9 August 2015

Request Management

I hate Request Management (RM) and I believe it is going away in SP 2016.

Issue I have seen with RM enabled:
  • Tenant Admin API can't provision Site Collections (point to the WFE's and it works)
  • Workflow sometimes don't start
  • Removing RM improved performance on an Extranet
  • Distributed Cache - One client had Distributed Cache intermittent issues.  User had to re-authenticate using STS.  As the RM was hit 1st and using distributed cache and then picking 1 of several WFE's, the issue was twice as likely to occur.  Used the NLB to direct traffic to the WFE's and the number of re-auths halved.