CTS4743 FINAL STUDY GUIDE

Which of the following is true about application development & infrastructure teams/approaches as it relates to troubleshooting?

- A disadvantage to an infrastructure focused approach is that you may end up chasing issues not related to the problem at hand - Even if a problem appears to be application related, infrastructure personnel should remain engaged - Both application and infrastructure approaches are appropriate and can be followed concurrently - An infrastructure focused approach to troubleshooting would include checking system capacity early in the process

Which of the following are true about CPU, I/O, RAM and Network constraints?

- CPU constraints can be addressed by tuning the application, increasing CPU power or spreading the workload - Network performance issues are more likely to be rooted outside of the host experiencing the delays - When a system is RAM constrained, the swapping rate and kernel time on the operating system would be high

Which "IT Infrastructure Support" teams are most likely to work directly with the application development teams?

- DBAs - Web Hosting - Server Engineering

Which concepts are considered a core feature/expectation of cloud computing?

- Elastically scalable - Metered - Provider managed hardware & physical environment - Software defined - Self-service

Which of the following statements are considered IT troubleshooting steps?

- Ensure a clear understanding of the problem and its history - Isolate the cause of the problem - Devise the best approach to address the problem - Verify that a problem actually exists

Which of the following statements are considered IT troubleshooting principles?

- Ensure clarity of symptoms/evidence/actions - Suppress any assumptions - Do not make things worse - Use reductive problem isolation techniques

Which of the following statements are true?

- ITIM (IT Infrastructure monitoring) tools allow you to review the statistics of many servers through one interface and provide historical trend reporting - Hypervisors contain a "Hardware abstraction layer" while containers do not - On both Windows & Linux, many utilities require administrative privileges - Having baseline metrics for comparison when performance is acceptable is a great way to determine if you have a problem

Which of the following statements are true about programming & database concepts?

- Platforms like IIS and WebSphere offer services like security, load balancing and protocol abstraction - Locking and poorly executing queries are two of the most common issues experiences with database servers - Even with modern database systems query optimization is still needed from time to time

Which of the following statements are considered IT troubleshooting goals?

- Saving evidence for root cause determination - Getting users working again - Determining root cause

Which of the following are dimensions of problems/constraints that should be considered when trying to isolate a problem?

- Single system vs. Multiple systems vs. System interaction - CPU vs. I/O vs. RAM vs. Network Constraints - Hard vs. Soft Constraints - Sporadic vs. Persistent

Which of the following are emerging industry trends affect most Enterprise IT Organizations today?

- Software Defined Infrastructure - DevOps - Cloud Computing

Which of the following statements are true about networking concepts?

- Symmetric encryption algorithms use the same key for encryption & decryption - Ethernet switches maintain a table of MAC addresses belonging to the ports on the switch - A layer 3 firewall is basically a router with special software to drops packets based on definitions provided

Which of the following statements are true about Operating System Concepts?

- The "Process" is the primary logical unit of an operating system - Hardware decoupling & automatic failover are two of the primary advantages of virtualization - Windows & Linux both work with hierarchical file systems

Which of the following statements are true about application protocols?

- Unlike SOAP, REST is not a protocol, but instead more of an architectural style of API programming - An advantage to storing the HTTP session state in an external database is that any request can go to any application server in the cluster - In-browser developer tools have an advantage over Fiddler and Wireshark because they process information post decryption - In a large enterprise, changes to AD (Active Directory) may not instantaneously replicate to all domain controllers

Which of the following are true about networking?

- Wireshark can track UDP communications or TCP conversations such that they can be graphed (for throughput, roundtrip time, etc) colorized, used as a filter, etc. - In order for two devices to share a VIP for failover purposes, the two devices must be available on the same broadcast domain - There could be multiple processes listening on the same port on a server as long as the IP address or protocol is different

Match the HTTP response code number to its category.

1xx = Informational: The request was received, continuing process 2xx = Successful: The request was successfully received, understood, and accepted 3xx = Redirection: Further action needs to be taken in order to complete the request 4xx = Client Error: The request contains bad syntax or cannot be fulfilled 5xx = Server Error = The server failed to fulfill an apparently valid request

Match the key statistic to the type to constraint it should be used to identify (there will be multiple matches)

CPU = Processor Queue length divided by number of processors I/O = I/O queue length I/O = CPU I/O wait % None = Disk space used Network = Network Bandwidth used None = CPU uptime CPU = CPU utilization % Memory = Paging swap rate

Match the Technology to it's description

DHCP, DNS = UDP-based broadcast protocol that provides IP addresses to hosts (typically pcs, hosts, IoT devices) Framework = Software providing generic functionality to ease the burden of common programing tasks Instrumentation = Ability to monitor or measure the level of an application's performance, to diagnose errors, and to write trace information SAN = Storage infrastructure consisting of a dedicated network (typically fiber channel) and storage devices NAT = Converts a private IP address to a public IP address and vice versa ARP = IP to MAC Address matching for local network communications

Match the Cloud term to its definition

Fog Computing = A relatively new paradigm which focuses on offloading or moving processing and storage to endpoint devices consuming cloud services SaaS = A cloud service offering whereby a fully functional application is provided to the customer with only application configuration options/Customizations are available EC2 = AWS' cloud computing offering Public Cloud = Refers to a cloud computing deployment model where services are offered by a third-party vendor independently of corporate/enterprise IT Hybrid Cloud = Refers to a cloud computing deployment model where services are offered by both third-party vendors and corporate/enterprise IT IaaS = A cloud service offering whereby virtual computing (VMs) are provided PaaS = A cloud service offering whereby a specific type of technology function (e.g. database, application server) is provided

Match the OSI Layer(s) to the type of communication

Layer 2 = Device to Device Layer 3 = Host to Host Layer 4 = Process to Process Layer 5-7 = Application to Application

Match the key statistic to the tool on Windows which would be most appropriate to help you measure it (there will be multiple matches)

Perfmon = Processor queue length Task Manager, Resource Monitor, Perfmon = Per process CPU utilization Resource Monitor, Perfmon = I/O queue length by disk Perfmon = Pages in & out per second Regedit = View/Edit registry entries Resource Monitor, Perfmon = Per process network bandwidth used Task Manager = CPU uptime netstat = Which processes are listening on which ports System Information = Number & type of physical CPUs Event Viewer = View application & system logs

You use the ping command with my.fiu.edu. Assuming no domain search list, place the steps that occur to find the IP address to use.

Step 1 = OS looks in local hosts file for "my.fiu.edu"; If found then use IP Address(es) Step 2 = OS looks in local DNS cache for "My.fiu.edu"; If found and TTL has not expired , uses IP address(es) Step 3 = OS makes request to local DNS server(s) for "my.fiu.edu" Step 4 = Local DNS server looks in local DNS cache for "my.fiu.edu"; If found and TTL has not expired, Uses IP address(es) Step 5 = If not found, local DNS server then looks for "fiu.edu" authoritative servers in local cache; if found and TTL has not expired, then uses IP address(es) to request IP address(es) for "my.fiu.edu" to those servers Step 6 = If "Fiu.edu" authoritative servers are not in cache, then local DNS server makes request to ".edu" root domain servers for IP address(es) of "fiu.edu" authoritative DNS server(s) Step 7 = Local DNS Server makes request to ".edu" root domain servers for "fiu.edu" authoritative DNS server Step 8 = ".edu" root server looks in its database for "fiu.edu" and returns IP address(es) if found or "name not found" if not Step 9 = Once known, local DNS server makes request to "Fiu.edu" authoritative server(s) for "my.fiu.edu" Step 10 = "fiu.edu" authoratative server looks in its database for "my.fiu.edu" and returns IP address(es) if found or "name not found" if not

Match the tool to the functionality:

certmgr = Windows GUI-based tool that allows you to view all of the installed certs on a system as well as add/remove certs from a system curl = Command line utility available for Linux, Windows & MacOS to access all sorts of protocols (not just HTTP) without user intervention - can test POST cmds tcpdump = Linux command line tool that allows you to perform a packet capture Fiddler = GUI-based proxy that can intercept all HTTP/HTTPS traffic and analyze it wget = Command line tool available on linux or Windows that allows you to make an HTTP GET requests w/o user interaction openssl = Command line program available on Linux (most common), Windows and MacOS that you can use to display certificates, convert certificate formats, create private/public key pairs, etc. Postman = GUI that allows you to format any kind of HTTP request and save it for future use as well as to share with others - can test POST cmds Wireshark = GUI-based packet capture analysis tool

Match the key statistic to the tool on Linux which would be most appropriate to help you measure it (there will be multiple matches)

vmstat = Processor queue length of runnable tasks top = Per process CPU utilization iostat = I/O Queue length by disk vmstat = Paging swap rate df = Disk space used iftop = Per process network bandwidth used top = CPU uptime netstat = Which processes are listening on which ports lscpu = Number of CPUs