AWS: Instance Types : Instance Families : Instance Sizes : Instance Pricing : EC2

https://aws.amazon.com/ec2/instance-types/

https://aws.amazon.com/ec2/instance-explorer

Instance type	Instance   size	Hypervisor	vCPUs	Architecture	Cores	Threads   per core	Sustained   clock speed (GHz)	Memory   (GiB)	Network performance	Maximum   number of network interfaces	IPv4 addresses per interface	IPv6 addresses per interface	On-Demand   Linux pricing
c5.4xlarge	4xlarge	nitro	16	x86_64	8	2	3.4	32	Up to 10 Gigabit	8	30	30	0.68 USD per Hour
c5.2xlarge	2xlarge	nitro	8	x86_64	4	2	3.4	16	Up to 10 Gigabit	4	15	15	0.34 USD per Hour
c5.xlarge	xlarge	nitro	4	x86_64	2	2	3.4	8	Up to 10 Gigabit	4	15	15	0.17 USD per Hour
c5.large	large	nitro	2	x86_64	1	2	3.4	4	Up to 10 Gigabit	3	10	10	0.085 USD per Hour

Analytics

• Elasticsearch Service  [Amazon Elasticsearch Service]
• MSK  [Amazon Managed Streaming for Apache Kafka]

https://aws.amazon.com/ec2/instance-types/

n/w performance and Clock Speed -  may stay same  in a instance family.

Instance Family : Processor Speed /N.W Performance:  a1,t2, t3 [General Purpose]          c4, c5 [Compute Optimised]                   [Memory Optimized/RAM]           [Accelerated Computing/HW Accelerator]     [Storage Optimized/EBS]

Instance Size :  vCPU, Cores,  Memory(RAM)    :    nano, micro, small, medium, large, xlarge, 2xlarge, 4xlarge

30.5 Days

Large has 4GB RAM, 1 Core, 2 VCPUs

similarly, xlarge has 8 GB RAM, 2 Core, 4 VCPUs

n/w performance and Clock Speed -  may stay same  in a instance family.

Burst is related to EC2 Performance

Amazon EC2 allows you to choose between Fixed Performance Instances (e.g. M5, C5, and R5) and Burstable Performance Instances (e.g. T3). Burstable Performance Instances provide a baseline level of CPU performance with the ability to burst above the baseline.

New Generation is cheaper as compared to Old/deprecated - if other features stay same.

Linux: Checksum :sha256

https://www.baeldung.com/linux/sha-256-from-command-line

Azure:Devops Stakeholder:Basic Access

https://stackoverflow.com/questions/48863308/in-vsts-how-to-move-access-level-from-stakeholder-to-basic-access

https://docs.microsoft.com/en-us/azure/devops/organizations/security/access-levels?view=azure-devops

Supported access levels

Assign users or groups of users to one of the following access levels:

• Stakeholder: Provides partial access, can be assigned to unlimited users for free. Assign to users with no license or subscriptions who need access to a limited set of features.
• Basic: Provides access to most features. Assign to users with a Visual Studio Professional subscription, an Azure DevOps Server CAL, and to users for whom you're paying for Basic access in an organization.
• Basic + Test Plans: Provides access to all features included in Basic, as well as Azure Test Plans. Assign to users with a Visual Studio Test Professional or MSDN Platforms subscription, and to users for whom you're paying for Basic + Test Plans access in an organization.
• Visual Studio subscription: Assign to users who already have a Visual Studio subscription. The system automatically recognizes the user's subscription—Visual Studio Enterprise, Visual Studio Professional, Visual Studio Test Professional, or MSDN Platform—and enables any other features that are included in their subscription level. If you assign Basic or Stakeholder, they also receive their Visual Studio subscription benefits upon sign-in.

Linux: Unlock User

https://www.2daygeek.com/lock-unlock-disable-enable-user-account-linux/

id <username>

passwd --status <username>

passwd -u <username>

usermod --unlock <username>

AWS : Mount EFS on EC2 - Part II - V Important

 sudo mkdir -p /efs

sudo chmod -R ugo+rwx /efs     

ls -ld /efs 

sudo vi /etc/fstab

fs-face524e.efs.us-east-1.amazonaws.com:/ /efs nfs4 rw,intr,hard,_netdev,nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2,noresvport

sudo mount -a

sudo reboot now

chmod -R 777 /efs  is not safer

chmod -R ugo+rwx /efs is safer - Does not override SETUID AND SETGID BITS - Just Appends permissions

https://unix.stackexchange.com/questions/296675/is-chmod-r-ugorwx-safer-than-chmod-r-777

cd / && sudo umount /efs && sudo mv /efs /fileshare && sudo chmod ugo+w /fileshare  && cat /etc/fstab 

sudo sed  -i 's+/efs+/fileshare+g' /etc/fstab 

sudo mount -a && sudo reboot now

ls -l /fileshare 

df -h

ls -l /fileshare ; df -h

ls -l /fileshare && df -h

umount /efs 

sudo mv /efs /fileshare

sudo chmod ugo+w /fileshare

sudo vi /etc/fstab

sudo reboot now

https://www.cyberciti.biz/faq/how-to-use-sed-to-find-and-replace-text-in-files-in-linux-unix-shell/

sudo sed   's/efs/fileshare/g' /etc/fstab   //Replace content and its temporary

sudo sed   's+/efs+/fileshare+g' /etc/fstab  // Change Delimiter

sudo sed  -i 's+/efs+/fileshare+g' /etc/fstab //-i save changes to file/stream

sudo sed  -e '/fs-face524e/s/fileshare/helloooo/' /etc/fstab //Replace only if lines contain specific string "fs-face524e"

How to replace a string in file in Linux

https://www.cyberciti.biz/faq/how-to-use-sed-to-find-and-replace-text-in-files-in-linux-unix-shell/

sudo sed   's/efs/fileshare/g' /etc/fstab   //Replace content and its temporary

sudo sed   's+/efs+/fileshare+g' /etc/fstab  // Change Delimiter

sudo sed  -i 's+/efs+/fileshare+g' /etc/fstab //-i save changes to file/stream

sudo sed  -e '/fs-face524e/s/fileshare/helloooo/' /etc/fstab //Replace only if lines contain specific string "fs-face524e"

Sort PS output

https://serverfault.com/questions/27887/how-to-sort-ps-output-by-process-start-time/27900

ps -ef --sort=start_time