AWS is an Amazon company with lots of openings for fresh talent, open to fresh ideas, innovation. Amazon web services the cloud based service that has migrated infrastructure from physical data center onto online cloud has been hiring engineers in various capacity including cloud support associate, cloud engineer, senior cloud support engineer, cloud architect, support manager etc. As a fresh graduate out of college this is a lucrative better career option you can eye on. Here we have proposed some interview questions that will help you crack the AWS interview including aws cloud support engineer interview questions. The interview questions does overlap with AWS cloud support associate, AWS cloud support engineer, AWS cloud architect as all these positions demand good knowledge, skill and expertise in Linux/UNIX OS,networking basisc to start with.
Note that these are not actual interview questions and this is just an aid prepared based on AWS stack analysis, job role responsibilities advertised by them in popular websites
These are some of the interview questions that you can expect during interview of AWS cloud support engineer, aws cloud support associate, AWS cloud support manager. We have analysed the technology stack, current job openings and created this based on them. These are not actual interview questions and has nothing to do with them
1) Why should we consider AWS? How would you convince a customer to start using AWS?
Primary advantage is going to be cost savings. As a customer support engineer your job role involves talking to current customers, prospective customers to help them determine if they really have to move to AWS from their current infrastructure. In addition to providing convincing answer in terms of cost savings it would be better if you give them real simple explanation of flexibility, elastic capacity planning that offers option of pay as you use infrastructure, easy to manage AWS console etc
2) What is your current job profile?How would you add value to customer?
Though AWS is looking to hire fresh talent for cloud support engineer openings, if you have some work experience in infrastructure side of business say system administrator, network administrator, database administrator, firewall administrator, security administrator, storage administrator etc you are still a candidate to be considered for interview.
All they are looking for is infrastructure knowledge in overall, little knowledge about different tech stack , how they inter-operate, what will it be like once the infrastructure is in web rather than physical data center.
If you don’t have experience with AWS don’t worry. Try to leverage the ways and means you did adopt to solve customer support calls both internal and external to let them know how you can bring value to the table.
Have some overview on how different components of infrastructure interact.
AWS wants to know your pro-active measure towards customer relationship. Say, if you are going to discuss a project or an issue with customer , it would be better if you have some preparatory work that comes handy rather than being reactive. Value addition comes in terms of recommending the best solution , utilization of services in AWS that will help them make decision easy and fast
3) Do you know networking?
Make sure you can be from many different backgrounds say from development, infrastructure, QA, customer support , network administration, system administration, firewall administration, system administration etc. You should know networking. Cloud is network based and to fix the application issues escalated, networking knowledge is very important
4) What networking commands do you make use of on daily basis to fix issues?
When we work with servers be it physical or virtual first command that comes handy to locate the request response path taken would be traceroute. In windows systems equivalent command is tracert
There are some more important interesting commands – ping, ipconfig, ifconfig that talks about network communication, network address, interface configuration etc
DNS commands – nslookup, Lookup of /etc/resolv.conf file in Linux systems to get details on DNS
5) What is the advantage of using TCP protocol?
TCP is used to exchange data reliably . IT used mechanisms of sequence and acknowledgment, error detection, error recovery. This comes with advantage of reliable application but comes with cost of hit in transmission time
6) What is UDP?
User datagram protocol called UDP is a connection less protocol that can be used for fast efficient applications that need less time compared to TCP
7) Do you know how an internet works in your environment?
This can be your home or office. Learn more on modem and its utilization in connection establishment
8) What is a process? How do you manage processes in Linux:-
In Linux/Unix based OS process is started or created when a command is issued. In simple terms while a program is running in an OS an instance of the program is created. This is the process. To manage the processes in Linux process management commands come handy
ps – this is the commonly used process management command to start with. ps command provides details on currently running active processes
top – This command provides details on all running processes. ps command lists active processes whereas top lists all the processes (i.e) activity of processor in real-time. This includes details on processor and memory being used
kill – To kill a process using the process id kill command is used. ps command provides details on process id. To kill a process issue
kill pid
killall proc – This command is same as kill command. To kill all the processes by name proc we can use this
9) Give details on foreground and background jobs command in Linux:-
fg – this command brings most recent job to foreground. Typing the command fg will resume most recently suspended job
fg n – This command brings job n to the foreground. If a job is recently back grounded by typing fg 1 this can be brought foreground
bg – This command is used to resume a suspended program without bringing it to foreground. This command also provides details on list of stopped jobs as well as current background jobs
10) How to get details on current date and time in Linux?
Make use of the command date that shows details on current date and time. To get current month’s calendar use cal command
uptime – shows current uptime
11) What is difference between command df and du?
In linux both df and du are space related commands showing system space information
df – this command provides details on disk usage
du – To get details on directory space usage use this command
free – this command shows details on memory and swap usage
12) What are the different commands and options to compress files in Linux?
Lets start with creating a tar and name it test.tar containing the needed files
tar cf test.tar files
Once the tar is available, uploaded on AWS there is a need to untar the files. Use the command as follows:
tar xf file.tar
We can create a tar with gzip compression that will minimize the size of files to be transferred and creates test.tar.gz at the end
tar czf test.tar.gz files
To extract the gzipped tar compressed files use the command:
tar xzf test.tar.gz
Bzip2 compression can be used to create a tar as follows
tar cjf test.tar.bz2
To extract bzip2 compressed files use
tar xjf test.tar.bz2
To simply make use of gzip compression use
gzip testfile – This creates testfile.gz
To decompress testfile.gz use gzip -d testfile.gz
13) Give examples on some common networking commands you have made use of?
Note that AWS stack is primarily dependent on linux and over the cloud architecture makes it heavily network dependent. As a result AWS interview could be related to networking irrespective of your system admin, database admin, bigdata admin background. Learn these simple networking commands:
When a system is unreachable first step is to ping the host and make sure it is up and running
ping host – This pings the host and output results
Domain related commands as AWS has become preferred hosting for major itnernet based companies, SaaS firms
To get DNS information of the domain use – dig domain
To get whois information on domain use – whois domain
Host reverse lookup – dig -x host
Download file – wget file
To continue stopped download – wget -c file
14) What is your understanding of SSH?
SSH the secure shell is widely used for safe communication. This is a cryptographic network protocol used for operating network services securely over an unsecured network. Some of the commonly used ssh commands include
To connect to a host as a specified user using ssh use this command:
ssh username@hostname
To connect to a host on a specified port make use of this command
ssh -p portnumber username@hostname
To enable a keyed or passwordless login into specified host using ssh use
ssh-copy-id username@hostname
15) How do you perform search in Linux environment?
Searching and pattern matching are some common functions that typically happens in Linux environment. Here are the Linux commands:
grep – Grep command is the first and foremost when it comes to searching for files with pattern. Here is the usage:
grep pattern_match test_file – This will search for pattern_match in test_file
Search for pattern in directory that has set of files using recursive option as follows – grep -r pattern dir – Searches for pattern in directory recursively
Pattern can be searched in concatenation with another command (i.e) output of a command can be used as input for pattern search and match – first command| grep pattern
To find all instances of a file use locate command – locate file
16) Give details on some user related commands in Linux:-
Here are some user related Linux commands:
w – displays details on who is online
whoami – to know whom you are logged in as
finger user – displays information about the user
17) How to get details on kernel information in Linux?
uname -a command provides details on kernel information
18) How to get CPU and memory info in Linux machine?
Issue the following commands:
cat /proc/cpuinfo for cpu information
cat /proc/meminfo for memory information
19) What are the file system hierarchy related commands in linux?
File system hierarchy starting with raw disks, the way disks are formatted into files, files are grouped together as directory all are important for cracking AWS interview. Here are some file system hierarchy related commands that come handy
touch filename – creates a file with name filename. This command can also be used to update a file
ls- lists the directories
ls -al – All files including hidden files are listed with proper formatting
cd dir – change to specified directory
cd – Changes to home directory
pwd – called present working directory that shows details on current directory
Make a new directory using mkdir command as follows – mkdir directory_name
Remove file using rm command – rm file – removes file
To delete directory use -r option – rm -r directory_name
Remove a file forcefully using -f option – rm -f filename
To force remove directory use – rm -rd directory_name
Copy the contents from one file to another – copy file1 file2
Copy the contents across directory use – cp -r dir1 new_dir – If new directory does not exist create this first before issuing copy command
Move or rename a file using mv command – mv file1 new_File
If new_Dir is a file that already exists new_File will be directory into which file1 will be moved into
more filename – output the contents of the file
head file – output the first 10 lines of the file
tail file – output the last 10 lines of the file
tail -f filename – output the contents of the file as it grows, to start with display last 10 lines
Create symbolic link to a file using ln command – ln -s file link – called soft link
20) What command is used for displaying manual of a command?
Make use of the command man command_name
21) Give details on app related commands in linux:-
which app – shows details on which app will be run by default
whereis app – shows possible locations of application
22) What are the default port numbers of http and https?
Questions on http and https port number is first step in launching webapp while customer reports an issue
Default port number of http is 80 (or) 8080
Default port number of https is 443
23) What is use of load balancer?
Load balancer is used to increase the capacity and reliability of applications. What capacity means is number of users connecting to applications. Load balancer distributes the traffic network and application traffic across many different servers increasing application capacity
24) What is sysprep tool?
System preparation tool comes as free tool with windows that can be accessed from %systemroot%\system32\sysprep folder. IT is used to duplicate, test and deliver new installation of windows based on established installation
25) User is not able to RDP into server. What could be the reason?
Probable reason is that user is not part of remote desktop users local group of the terminal servers
26) How would you approach a customer issue?
Most work of AWS support engineer involves dealing with customer issue.As with any other support engineer AWS engineer should follow approach of question customer, listen to them, confirm what you have collected. This is called QLC approach much needed step to cover details on issue description and confirm it
27) What types of questions can you ask customer?
A support engineer can ask two types of questions
1) Open ended questions – In this case your question will be single statement, answer you expect from customer is detailed
2) Closed questions – In this case your question will have answers yea (or) No, true (or) false type answers, single word answer in some cases
28) How do you consider customer from AWS technology perspective?
Even though the customer can be long standing customer of AWS, always think of customer as common man with no knowledge of AWS to talk more to them, explain more details to them to get correct issue description statement
29) Give details on operators in linux?
> – greater than symbol is input re-direction operator used to write content as input into file. Typically this is used to redirect the output of command into logfile. IF file already exists the contents are overwritten and only last recent content is retained
>> – this is same as input redirection except that this is appending content of a file if the file already exists
30) Explain difference between hardlink and softlink in simple terms?
Hardlink is link to inode that talks about file contents, softlink is link to filename. If filename changes the changes are not reflected. For both hard and soft link ln command is used. In case of hardlink it will be simply ln, for soft link ln -s option is used
31) What are some common linux commands AWS engineer should be aware of?
1) cat – This is plain simple command to access a file in UNIX
2) ls – Provides details on list of files and directories
3) ps – The process command provides details on list of processes in the system
4) vmstat – Virtual memory statistics comes handy during performance tuning
5) iostat – Command to determine I/O issues
6) top – This command provides details on top resource consuming processes
7) sar – This is a UNIX utility mainly used for tuning purpose
8) rm – This command is used to remove files
9) mv – moving the files and directories
cd – Enables us to change directories
date – gives us the time and date
echo – we can display text on our screen
grep – It is a pattern recognition command.It enables us to see if a certain word or set of words occur in a file or the output of any other command.
history – gives us the commands entered previously by us or by other users
passwd – this command enables us to change our password
pwd – to find out our present working directory or to simply confirm our current location in the file system
uname – gives all details of the system when used with options. We get details including systemname,kernel version etc.
whereis – gives us exact location of the executable file for the utility in the question
which – the command enables us to find out which version(of possibly multiple versions)of the command the shell is using
who – this command provides us with a list of all the users currently logged into the system
whoami – this command indicates who you are logged in as. If user logs in as a userA and does a su to userB,whoami displays userA as the output.
man – this command will display a great detail of information about the command in the question
find – this command gives us the location of the file in a given path
more – this command shows the contents of a file,one screen at a time
ps – this command gives the list of all processes currently running on our system
cat – this command lets us to read a file
vi – this is referred to as text editor that enables us to read a file and write to it
emacs- this is a text editor that enables us to read a file and write to it
gedit – this editor enables us to read a file and write to it
diff – this command compares the two files, returns the lines that are different,and tells us how to make the files the same
export – we can make the variable value available to the child process by exporting the variable.This command is valid in bash,ksh.
setenv – this is same as export command and used in csh,tcsh
env – to display the set of environment variables at the prompt
echo <$variablsname> – displays the current value of the variable
source – whenever an environment variable is changed, we need to export the changes.source command is used to put the environment variable changes into immediate effect.It is used in csh,tcsh
.profile – in ksh,bash use . .profile command to get same result as using source command
set noclobber – to avoid accidental overwriting of an existing file when we redirect output to a file.It is a good idea to include this command in a shell-startup file such as .cshrc
32) What are the considerations while creating username/user logins for Security Administration purpose?
It is a good practice to follow certain rules while creating usernames/user logins
1) User name/user login must be unique
2) User name/user login must contain a combination of 2 to 32 letters, numerals, underscores(_),hyphens(-), periods(.)
3) There should not be any spaces/tab spaces while creating user name/usr logins
4) User name must begin with a letter and must have atleast one lowercase letter
5) Username must be between three to eight characters long
6) It is a best practice to have alphanumeric user names/user logins. It can be a combination of lower case letters, upper case letters, numerals, punctuation
33) Give details on /etc/profile the system profile file and its usage in linux environment:-
.This is another important UNIX system administration file. This file has much to do with user administration. This file is run when we first log into the system.This is system profile file. After this user profile file is run. User profile is the file wherein we define the users environment details.Following are teh different forms of user profile files :
.profile
.bash_profile
.login
.cshrc
/home/username is the default home directory.User’s profile file resides in the user’s home directory.
34) How to perform core file configuration in Linux environment?
Lets consider a linux flavor say solaris. Core File Configuration involves the following steps. We need to follow the steps given below to configure the core file.
1) As a root user, use the coreadm command to display the current coreadm configuration :
# coreadm
2) As a root user, issue the following command to change the core file setup :
# coreadm -i /cores/core_new.%n.%f
3) Run the coreadm command afain to verify that the changes has been made permanent
# coreadm
The O/P line “init core file pattern : ” will reflect the new changes made to the corefile configuration.
From solaris 10 onwards, coreadm process is configured by the Service Management Facility (SMF) at system boot time.We can use svcs command to check the status .The service name for coreadm process is :
svc:/system/coreadm:default
35) How do you configure or help with customer printer configuration?
Administering Printers details the steps needed to administer a printer.
Once the printer server and printer client is set up, we may need to perform the following administrative tasks frequently :
1) Check the status of printers
2) Restart the print scheduler
3) Delete remote printer access
4) Delete a printer
36) How is zombie process recognized in linux and its flavors? How do you handle zombie process in linux environment?
Zombie Process in UNIX/LINUX/Sun Solaris/IBM AIX is recognized by the state Z.It doesn’t use CPU resources.It still uses space in the process table.
It is a dead process whose parent did not clean up after it and it is still occupying space in the process table.
They are defunct processes that are automatically removed when a system reboots.
Keeping OS and applications up to date and with latest patches prevents zombie processes.
By properly using wait() call in parent process will prevent zombie processes.
SIGCHLD is teh signal sent by child to parent upon task completion and parent kills child(proper termination).
kill -18 PID – Kills childs process
37) What is the use of /etc/ftpd/ftpusers in Linux?
/etc/ftpd/ftpusers is used to restrict users who can use FTP(File Transfer Protocol).Ftp is a security threat as passwor is not encrypted while using ftp. ftp must not be used by sensitive user accounts such as root,snmp,uucp,bin,admin(default system user accounts).
As a security measure we have a file called /etc/ftpd/ftpusers created by default. The users listed in this file are not allowed to do ftp.The ftp server in.ftpd reads this file before allowing users to perform ftp. If we want to restrict a user from doing ftp we may have to include their name in this file.
38) Have you ever helped a customer restore a root file system in their environment?
Restoring root file system (/) Â provides steps we need to follow to restore the root file system (/ system) in SPARC and x86 (intel) machines.
1) Log in as root user. It is a security practice to login as normal user and perform an su to take root user (super user) role.
2) Appearance of # prompt is an indication that the user is root
3) Use who -a command to get information about current user
4) When / (root filesystem) is lost because of disk failure. In this case we boot from CD or from the network.
5) Add a new system disk to the system on which we want to restore the root (/) file system
6) Create a file system using the command :
newfs /dev/rdsk/partitionname
7) Check the new file system with the fsck command :
fsck /dev/rdsk/partitionname
8) Mount the filesystem on a temporary mount point :
mount /dev/dsk/devicename /mnt
9) Change to the mount directory :
cd /mnt
10) Write protect the tape so that we can’t accidentally overwrite it. This is an optional but important step
11) Restore the root file system (/) by loading the first volume of the appropriate dump level tape into the tape drive. The appropriate dump level is the lowest dump level of all the tapes that need to be restored. Use the following command :
ufsrestore -rf /dev/rmt/n
12) Remove the tape and repeat the step 11 if there is more than one tape for the same level
13) Repeat teh step 11 and 12 with next ddump levels. Always begin with the lowest dump level and use highest ump level tape
14) Verify that file system has been restored :
la
15) Delete the restoresymtable file which is created and used by the ufsrestore utility :
rm restoresymtable
16) Change to the root directory (/) and unmount the newly restored file system
cd /
umount /mnt
17) Check the newly restored file system for consistency :
fsck /dev/rdsk/devicename
18) Create the boot blocks to restore the root file system :
installboot /usr/platform/sun4u/lib/fs/ufs/bootblk /dev/rdsk/devicename — SPARC system
installboot /usr/platform/`uname -i`/lib/fs/ufs/pboot /usr/platform/`uname -i`/lib/fs/ufs/bootblk /dev/rdsk/devicename — x86 system
19) Remove the last backup tape, and insert a new tape onto which we can write. Make a dump level 0 backup of the newly restored system by issuing the following command :
ufsdump 0ucf /dev/rmt/n /dev/rdsk/deviceName
This step is needed because ufsrestore repositions the files and changes the inode allocations – the old backup will not truly represent the newly restored file system
20) Reboot the system :
#reboot (or)
# init 6
System gets rebooted and newly restored file systems are ready to be used.
21) What is the monitoring and reporting tool that comes as part of AWS console?
Cloudwatch the tool listed under management section of AWS console helps with monitoring and reporting emtrics in AWS environment. Following metrics can be monitored as part of cloudwatch including
1) CPU
2) Disk utilization
3) Network
4) Status Check
In addition to the above mentioned metrics RAM the custom metric can be monitored using cloudwatch
22) Give details on status check in cloudwatch?
In an AWS environment status of both instance and system needs to be monitored. As such there are system status check as well as instance status check sections associated with each and every EC2 instance. As the name implies system status check makes sure that physical machines on which the instances have been hosted is in good shape. Instance status check is at the EC2 instance which literally translates to virtual machine in AWS environment
23) What happens if a failure is reported in status check section of AWS?
Depending on what type of failure has been reported following actions can be taken:
In case of system failure – Restart the virtual machine. In AWS terms, restart the EC2 instance. This will automatically bring up the virtual machine in a physical hardware that is issue free
Instance Failure – Depending on the type of failure reported in EC2 instance this can be stopping and starting of virtual machine to ix the issue. In case of disk failure appropriate action can be taken at operating system level to fix the issues
24) What is an EC2 instance in AWS?
This is the basic component of AWS infrastructure. EC2 translates to Elastic compute cloud. In real-time this is a pre-built virtual machine template hosted in AWS that can be chosen, customized to fit the application needs
This is the prime AWS service that eliminates a business necessity to own a data center to maintain their servers, hosts etc
25) What is an ephemeral storage?
An ephemeral storage is a storage that is temporary (or) non-persistent
26) What is the difference between instance and system status check in cloudwatch?
An instance status check checks the EC2 instance in an AWS environment whereas system status check checks the host
27) What is the meaning of EBS volume status check warning?
An EBS volume is degraded or severly degraded. Hence, a warning in an EBS environment is something that can’t be ignored as with other systems
28) What is the use of replicalag metric in AWS?
Replicalag is a metric used to monitor the lag between primary RDS the relational database service a database equivalent in AWS environment and the read replica the secondary database system that is in read only mode
29) What is the minimum granularity level that a cloudwatch can monitor?
Minimum granularity that cloudwatch can monitor is 1 minute. In most real-time cases 5 minute metric monitoring is configured
30) What is the meaning of ebs volume impaired ?
EBS volume impaired means that the volume is stalled or not available
31) Where is ELB latency reported?
In cloudwatch the latency reported by elastic load balancer ELB is available
32) What is included in EC2 instance launch log?
Once the EC2 instance is created, configured and launched following details are recorded in instance launch log:
Creating security groups – The result needs to be Successful. In case of issues the status will be different
Authorizing inbound rules – For proper authorization this should show Successful
Initiating launches – Again this has to be Successful
At the end we see a message that says Launch initiation complete
33) What will happen once an EC2 instance is launched?
After the EC2 instance has been launched it will be in running state. Once an instance is in running state it is ready for use. At this point usage hours which is typically billable resource usage starts. This keeps accruing until we stop or terminate our instance. NExt immediate step is to view instance
34) What is maximum segment size (mss)? How is this relevant to AWS?
The maximum segment size is the important factor that determines the size of an un fragmented data segment. AWS is cloud based and the products hosted are accessed via internet connection. For data segments to successfully pass through all the router during transit their size should be acceptable across routers. If they grow big the data segments get fragmented. This eventually leads to network slowness
35) How does a load balancer check the EC2 instance availability in an AWS environment?
Periodically load balancer sends pings, attempts connections, send requests to EC2 instances to cehck their availability. Often these tests are referred as health checks in an AWS environment
36) Give details on health check and status of instances in an AWS environment :-
In an AWS environment to check the status of EC2 instances the load balancer periodically sends pings, attempts connection, sends requests to EC2 instances. This process is referred to as health check in an AWS environment
If an EC2 instance is healthy and functioning normal at the time of health check the status will be InService
If an instance does not respond back this is unhealthy and its status will be OutOfService
37) What are the instances that are candidates to be part of health check?
If an instance is registered with a load balancer this is a candidate under health check process in AWS. This covers instances that are in both healthy and unhealthy statuses which are typically InService and OutOfService respectively
38) What happens when an instance in an AWS environment has been found to be in an unhealthy state?
The requests will not be routed to unhealthy instances by load balancer. Once the instance health is restored back to healthy status requests are routed here
39) What is IPSec?
IPSec refers to the internet protocol security that is used to securely exchange data over public network that no-one can view and read except the intended parties. IPSec makes use of two mechanisms that work together to exchange data in a secure manner over the public networks. Though both of these mechanisms are not mandate we can use just one or both togetehr. The two mechanisms of IPSec are
Authentication header – Used to digitally sign the entire contents of each packet that protects against tampering, spoofing, replay attacks. The major disadvantage of authentication header is that though this protects data packets against tampering the data is still visible to hackers. To overcome this ESP can be used
Encapsulating Security Payload – ESP provides authentication, replay-proofing and integrity checking by making use of 3 components namely ESP header, ESP trailer, ESP authentication block
40) What are the many different types of IPSec modes?
Tunnel more, transport mode are the two modes that we can configure IPSEc to operate in.Tunnel mode is the default mode and used for and used for communication between gateways like routers, ASA firewalls (or) at an end-station to a gateway. Transport mode is used for end-to-end communication between a client and a server, between a workstation and a gateway like telnet connection, remote desktop connection between a workstation and server over VPN etc
41) In a class B network give relationship between network /count and number of hosts possible :-
network
/count No of hosts possible
16 65536
17 32768
18 16384
19 8192
20 4096
21 2048
22 1024
23 512
24 256
25 128
26 64
27 32
28 16
29 8
30 4
42) In a class C network give relationship between network /count and number of hosts possible :-
network
/count No of hosts possible
24 256
25 128
26 64
27 32
28 16
29 8
30 4
43) You are a DBA and have been assigned task of migrating oracle database to AWS with minimal to no impact to source database. How will you achieve this?
Make use of Database Migration Service. This will help you migrate databases securely and easily. This tool enables live migration of data making sure source database is up and running during migration
