For the rest of this quiz, use the following application arc…

For the rest of this quiz, use the following application architecture description as the basis to answer the below questions: Overview – The application is called “CCAPP”.  It has a web-based front-end interface and exposes several services for other applications to utilize. Web Infrastructure – All the application components are written in .NET and deployed on 2 app pools on 3 IIS servers named WIIS1.acme.com (with IP 10.20.10.101), WIIS2.acme.com (with IP 10.20.10.102), & WIIS3.acme.com (with IP 10.20.10.103) – they each listen on port 80. One app pool is for the web-based user interface and utilizes the “/ccapp” virtual directory, while the other app pool is for the web services and uses the “/ccapp-apis” virtual directory The IIS servers are part of two pools (one for each virtual directory) front-ended by a load balancer. The load balancer exposes two VIPs (ccapp.acme.com with IP 204.153.78.20 for the user interface and ccapp-apis.acme.com with IP 204.153.78.21 for the web services) to the internet. The load balancer proxies the web servers and populates the X-Forwarded-For HTTP Header for both pools Both app pools are recycled in a rolling fashion (one IIS server at a time) each night There is no “session stickiness” because the session state is stored in a database Security & Network There is a firewall in between the load balancer and the IIS servers The application’s front-end interface is protected by an OAUTH cloud-based service that has a replicated copied of the company’s Active Directory. For any user to authenticate to the application it needs to be defined in AD and part of the ccapp-users group. The application’s web services are protected by IP-filtering (only certain IP addresses are allowed to connect to them) and application tokens (long strings) are individually shared with each client There is a firewall in between the IIS servers and the database server Database & Other external factors CCAPP utilizes a SQL Server database (IP 10.20.20.100) for its application data and its session state (only applicable to the user interface) CCAPP (UI & services) makes calls to internal web services that have their own web and database servers. The application also makes calls to web services on the Internet The application is 24×7, but also has a nightly batch job component that performs heavy updates for a couple of hours Transaction log backups occur every 30 minutes, differential backups nightly and full backups weekly on Sundays Index rebuilds and/or reorgs (depending on the state of each index) as well statistics updates are performed on a weekly basis as well The database is large (over 3TB) and replicated to another location asynchronously for disaster recovery purposes Personnel Assume you have access to a business user representative, an ITSM practitioner, server engineer, DBA, web hosting engineer, network engineer & an application developer Scenario #3 – Calls start coming in about generally poor performance with the “CCAPP” user interface.  The following is some initial information gathered. All screens/functions of the “CCAPP” application seem to be impacted Even the web services of the “CCAPP” application are performing poorly No blocked sessions on the database server No other applications appear to be impacted on the same web server or other servers in the same network segment Provide at least two distinctly different plausible causes and how to test for them (include tools to utilize or procedures to follow and what you would be looking for). – 10 points (5 extra credit points for each additional plausible root cause after the first three)
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