CTS4743

client-server

2layer and 2 tier app that uses a complex front end app communcating with a shared back end

web-based

3layers and 3 tiers in its basic form but can get complex; solves some of the issues with the client-server architecture

match the http response code number to its category

3xx - redirection 4xx- client error 1xx - informational 2xx - successful 5xx - server error

EC2

AWS' cloud computing offering.

Which of the following are emerging industry trends affect most IT enterprise organizations today?

Cloud computing DevOps Software defined infrastructure

NAT

Converts a private ip to a public ip

ARP

Ip to mac address for local network communcations

Which of the following disciplines are typically considered "IT infrastructure support"?

Network engineering Storage engineering Server engineering

SAN

Storage infrastructure consisting of a dedicated network and storage devices

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

The process is the primary logical unit of an operating system the process is the basic logical execution unit of an operating system. windows and linux both work with hierarchical file systems hardware decoupling and automatic failover are two of the primary advantages of virtualization.

DHCP

UDP based protocol that provides ip addresses to hosts

SaaS

a cloud offering whereby a fully functional application is provided to the customer with only application configuration options

Which of the following statements are true about networking concepts?

a layer 4 conversation requires 5 unique values. a layer 3 firewall is basically a router with special software to drop packets based on definitions provided. high number ports are typically reserved for well known server applications.

Fog computing

a new paradigm which focuses on offloading or moving processing and storage to endpoint devices

Instrumentation

ability to monitor or measure the level of an applications performance to diagnose errors

proxying

acts as a man in the middle

tunneling

allowing direct network later communication between devices that other could not communicate.

which of the following statements are true about application protocols.

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 description. unlike soap, rest is not a protocol but instead more of an architectural style of api programming. in a large enterprise changes to active directory may not instantaneously replicate to all domain controller.

which of the following is true about application architecture problems

application alyering influences but does not dictate application tiering. with a microservices application it is often simpler to focus on the tiers and layers of simialrty deployed servers. databse server proximity is typically important for client server applications as well as the app server of web based apps. latency and coldstarts are problems with some of the cloud native services

compare application first and infrastructure first

application first approach start with errors being generated by the application then work to isolate whatever is causing the problem at hand but it may take longer to find. infrastructure first starts by checking the monitoring tools for alarms or capacity issues on all related infrastructure components and looking for errors in system logs. you could get a very quick resolution to your problem but it may lead to red herrings as system monitors and logs often contain errors and warning not associated with the problem at hand.

message queuing

asynchronous communation between two process with guaranteed delivery

tunneling

can allow private ip addressed to communicate over the internet.

network segmentation

can be used to restrict the network level of guests

local load balancer

can perform health checking

job scheduling

can start programs based on date/time, creation of a file

Which concepts are not considered a core feature of cloud computing.

capital expense heavy. physically isolated. dedicated resources.

Given the fact that slow performance seems to be rooted in a particular server (you can choose whether it's Windows or Linux), describe five distinctly different actions you would take to identify the type of constraint occurring - include tools used and metrics analyzed. The more detail & examples provided, the more points you earn. (5 extra credit points for each additional action after the first five)

check if it is happening in other servers and compare what they have in common. check the cpu to what is going on with the server. see how the ram is doing. check the i/o latency. do some network monitoring because most network contraints can be perceived as poor performance of the server.

Assume there is a critical .NET web-based application that resides on three IIS servers, sits behind a load balancer, utilizes an Oracle database for its application data and stores its session state in a SQL Server database. You get a call that this application is suddenly performing very poorly for at least some users. Provide five distinctly different actions you could take to isolate where the performance problem resides, including the tools you would use for each (you can assume access to server, database & network administrators). The more detail & examples provided, the more points you earn. - 25 points (5 extra credit points for each additional action after the first five)

check if the cpu is high, if it is look at the top queries using the cpu to see if they can be optimized. there could also be blocking session, use oracle which lets you view all aspects of the database. using microsoft sequel server could help find in queries quickly check if there is spike in activity and see if there have been any recent changes in code. if the servers are load balanced determine if only one server is having the problem

PaaS

cloud offering a specific type of technology function is provided

IaaS

cloud offering where virtual computing are provided

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

cpu contstraints can be addressed by tuning the application, increasing the cpu power or spreading the workload. network performance issues are more likely to be rooted outside of the host experiencing delays. when a systems is ram constrained the swapping rate and kernel time on the operating system would be high.

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

cpu vs i/o vs ram vs network constraints. hard and soft constraints. sporadic vs persistent. single vs mutiple vs system interaction.

Which of the following statements are considered IT Troubleshooting goals?

determining root cause. saving evidence for root cause determination. getting users working again.

match the osi layers to the type of communcation

device to device - layer 2 host to host - layer 3 process to process - layer 4 application to application - layer 5-7

job scheduling

event based execution on program without user interaction

serverless/FaaS

fairly new popular subset of the cloud native application

business to business

focus is on adressing three key elements of integration.

load balancing

front end multiple servers that perform the same function only to sending traffic to the healthy ones.

which of the following statements are true

having baseline metric for comparison when performance is acceptable is a great way to determine if you have a problem. hypervisors contain a hardware abstraction layer while containers do not. itim tools allow you to review the statistics of many servers through one interface and provide historical trend reporting. on both windows and linux many utilities require administrative privileges.

what is true about networking

in order for two devices to share a vip for failover purposes the two devices must be available on the same broadcast domain. wireshark can track udp communications or tcp conversations such that they can be graphed for. there could be mutiple process listening on the same port on a server.

compare incident and problem management.

incident the primary goal is to restore the normal service operation as quickly as possible and to minimize the impact on business operations. prioed as p1,p2,p3. p1 being the highest. in problem the primary objectives are to prevent incidents from happening and minimize the impact of incidents. problems are related to repeated incidents.

Which of the following statements are considered IT Troubleshooting steps?

isolate the cause if the problem. devise the best approach to address the problem. ensure a clear understanding of the problem and its history.

terminal emulation

legacy character based application that can be deployed on 2, 3 or ntier

step 4

local dns looks in local dns cache for my.fiu.edu if found and ttl has not expired use ip addresses

cloud native

only utilize PaaS services without needing to rely on accessing any operating system

step 2

os looks in local dns cache for myfiuedu if found ttl has not expired, uses ip address

step 1

os looks in local hosts file for my fiu.edu if found then use ip address

step 3

os makes request to local dns server for my.fiu.edu

Match the key statistic to the tool on Windows which would be most appropriate to help you measure it

processor queue length - perfmon per process cpu utilization - task manger, resource manger, perfmon i/o queue length by disk - resource manager, perfmon pages in and out per second -perfmon view and edit registery - regedit per process network bandwidth used - resource manager, perfmon cpu uptime - task manager which processes are listening on which ports - netstat number and type of cpus - system information view application and system logs - event viewer

match the key statistic to the type of constraint it should be used to identify.

processor queue length divided by the number of processors- CPU I/O queue length - i/o cpu i/o wait percent - i/o disk spaced used - none network bandwidth used - network cpu uptime - none cpu utilization - cpu paging swap rate - memory

Match the key statistic to the tool on Linux which would be most appropriate to help you measure it

processor queue length of runnable tasks - vmstat per process cpu utilization - top i/o queue length by disk - iostat paging swap rate - vmstat disk space used - df per process network bandwidth used- iftop cpu uptime - top which processes are listening on which ports - netstat number of cpus - iscpu

multicloud

refers to a cloud computing model where services are offered by third party vendors independently of corporate IT

which of the following statements are true about programming and data base concepts

relational databases offer durability by comitted all changes to a log prior to updating the database. platforms like IIs and webspehere offer services like security, load balancing, and protocol abstraction. within a running process each thread maintains it's own call stack.

local load balancer

session stickiness

Match the potential problem to the type of platform it relates to:

sessions being blocked by other sessions due to locks - database server concurrent requests exceedd the amount allowed causing rejections and delays - both lack of code instrumentation causing difficulty isolating where the problem resides - web/app transaction log getting full - database long waits on remote resource calls - web/app poorly executing queries taking up a large amount of cpu and i/o- database low buffer cache hit - database broswer incompatibility - none error in logs indicate a product path is needed. - both

which is true about hosting platforms

sine html java and css can execute on the browser your code could be impacted by a different browser or even version poorly executing database queries can be solved by updating statistics. all requests to a web server are typically logged and can include the ip of the client. most often application servers also include at least a thing http webserver

Framework

software providing generic functionality to ease the burden of common programming tasks

soa and microserver

style of software design where you break up the business logic portion of your app into smaller independent portions

compare and contrast multitasking, processing, and threading.

tasking is when the os provides time to the cpu to run process based on certain factors processing is tasking on a larger scale. it goes across mutiple cpus so that many processes can run at the same time threading is when all the processes have one thread but the applications can be made so that once process can use more than one thread and use more of the cpu to get work done faster.

which is true about application architecture techniques

there are 2 common methods of employing session stickiness on a load balancer. due to its unattended anture, job scheduling requires thoughtful error checking. there could be multiple consumers and or producers for any given message queue. content delivery networks have evolved into a full reverse proxies that automatically pull updates, support dynamic content retrieval from backend server and can even include security features like ddos prevention and waf function

DNS

udp based protocol that provides ip addresses to hosts

global load balancer

used dns redirection to point the user to the vip that should be accessed.

web proxy

used to block users from accessing restricted sites

match the tool to the functionality

windows gui-based tool that allows you to view all the installed certs on a system. - certmgr command line utility available for linux window and mac to access all sorts of protocols without user intervention - curl linux command line that allows you to perform packetcapture - tcpdump gui based proxy intercept all https/https traffic and analyze it -fiddler command lone tool on linux and windows that allows you to make an a http get request - wget command line for linux mac and windows that you can use to display certs and create keys - openssl gui that alows you format any https request and save it for the future - postman fui based packet capture analysis - wireshark