AWS EC2 Flashcards
List the EC2 instance categories?
Spot Instance, On-Demand Instances, Reserved Instances.
What is an EC2 spot instance?
You can bid on unused EC2 capacity by using a spot instance, but a spot instance can be stopped and unallocated by AWS at any point in time.
What is a reserved instance?
You pay upfront for EC2 capacity and you are guaranteed to be able to use this capacity when you need it, even if the AWS region is at 100% capacity.
What is a on demand instance?
You use what you need and pay as you go.
When using a reserved instance are you guaranteed you will be able to provision the EC2 instance when need, even if the AWS region is at 100% capacity.
Yes
When using spot instances are you gaurenteed resources?
No
When using spot instance can the instance be stoped at any time?
Yes.
When using reserved instance can the instance be stoped at any time?
No.
When using on-demand instance can the instance be stoped at any time?
No.
With on demand instance are you gaurenteed resources
No.
Is a spot instance the best choice for a situation where the load is changing all the time and the workload can not be interupted?
No a better choice here would be on-demand instance.
What is AWS free tier?
When you sign up and during the first 12months you get some free resources with some restrictions, this is to help you learn.
Is spot instances a lower cost then other instance types?
Yes as you bit for unused capacity.
What sort of processes are best suited to spot instances?
Batch processes or tasks.
If you know you will need a instance 24/7 365, what instance type is best suited to get best value, the work load can not be interrupted.
Reserved as it gives you the low price as you pay upfront and are guarantee the resources.
`
No.
When you buy a reserved instance is it in all availability zones?
No it is for a single availability zone.
Can you transfer a reserved instances from one availability zone to another ?
Yes.
If you have a large reserved instance and you do not need it any more but need a number of smaller instances, what can you do?
You can create a number of small instances from a large reserved instance.
What is the default number of instances you can create ?
20
Mow many elastic IP do you get by default?
5
Where you reached the default max limits of EIP’s or Instances, what can you do to get more resources?
You can ask AWS to give you more resources, this typically takes 24hrs.
Is ES2 instances fault tolerant?
No you have to architect a solution with fault tolerance.
Dose ES2 instances integrate with IAM?
Yes
What is the easiest way for application running on a EC2 instance to use the AWS service API’s with out needing IAM keys?
Create a IAM role for EC2 instance.
What is EC2?
Elastic cloud compute.
Are you paying for compute resource when the VM is stopped?
No.
When a instances is stopped are you paying for any other resources used by the instance?
Storage used by EC2.
What are the EC2 classic instances sizes?
micro, small, medium, large.
If you what to stop some one stopping you instance by mistake, what can you do?
You can check the ‘terminate protection’ check box.
What is a EC2 instance created from?
AMI’s.
What are AMI’s?
An AMI is a sort of a template containing all the information required for creating one or more EC2 instances. The template(AMI) consists of,
- Owner
- Launch permissions
- Architecture (64-bit X86 or 64bit-ARM)
- Operating system
- Block devise mapping
Is it possible for you to create a custom AMI?
Yes, you can build a custom AMI for Linux and Windows.
What services do you use to give EC2 instances volumes?
EBS.
What do you pay for with EC2?
Compute time if the instance is powered on, storage, data transfer.
There are currently two places a EC2 instance can store data, what are they?
Instance store and EBS.
Where a instance is using a instance store and you stop the instance, will you data persist?
No when you stop a instance the data is gone/deleted.
Where is the data stored when the EC2 instance is using a instance store.
Data is tired on the local had disks of the server and not remote storage.
What is EBS?
Elastic block store.
Where do EBS volumes live in relation to EC2 instance?
The volume is remote from the EC2 instance?
What are provisioned IOPS in relation to EBS?
The ability to configure the amount of IOPS you required for you EBS volume.
How would you calculate MB transfer per second?
IOPS + 16K chunks = MB transfer per second.
What sort of application would benefit from provisioned IOPS?
Database applications, because of the random read and write patterns.
What is the min for provisioned iops?
100
What is the max provisioned IOPS?
64000
What is the min size of the EBS volume?
1GB
What is the max size of a EBS volume?
1TB
What raid is used for a EBS volume?
Raid0
Can you connect a EBS volume to more then one instance?
No.
Is EBS a object store?
No it is a block store.
Is a EBS volume local storage on the server where the EC2 instance is running?
No it is network attached storage and is remove from the EC2 instance.
What is pre-warming a EBS volume?
This is where AWS will preform a erase on the volume the first time the volume is used and this has a large impact on performance.
Is it possible to snapshot a EBS volume?
Yes
Where are snapshots stored?
?????
Do you pay for snapshot storage?
?????
Are EBS snapshots incremental or full?
Incremental.
Why would you take frequent snapshots?
To increase durability?
Do snapshots degrade application performance what they are happening?
Yes.
Will data persist on a EBS volume?
Yes.
What Linux command would you use to touch every block on the volume during pre-warming?
dd command.
How would you backup a EBS volume?
take a snapshot.
How can you move a EBS volume to another availability zone?
??
Can you schedule snapshots?
yes using the aws command line tools.
What is user data used (script) used for, in reference to EC2.
This is a script that is run at the beginning of VM boot up.
What is the cloud-init script used for, in reference to EC2.
This is a script that is run at the beginning of VM boot up.
How can you from a script or applications access the EC2 features?
API or execute use the CLI.
When you create a new EC2-Classic instance dose it get a public IP?
Yes
When you create a new EC2-Classic instance dose it get a private IP?
Yes
When you create a new EC2-Classic instance dose it get a CNAME?
Yes
When you start or stop the instance will the private IP change, when using EC2-Classic?
Yes
When you start or stop the instance will the public IP change, when using EC2-Classic?
Yes
When you start or stop the instance will the CNAME change, when using EC2-Classic?
Yes
How can you assign a static IP for a for a EC2-Classic?
Assign a elastic IP.
Is a elastic IP a public or private IP?
Public.
How many elastic IP’s can we assign to a EC2-Classice instance?
0ne per instance
What is the default number of elastic IP you get?
You get 5.
Can you request more elastic IP?
Yes.
When using elastic IP’s and you shutdown a instance, will the elastic ip change?
No.
Can you detach and reattach a elastic IP to a new EC2 instance?
Yes.
When you stop a instance is the elastic ip detached
yes and you will have to reattach it to the instance.
What is the elastic load balancer used for?
To distribute traffic between EC2 instances.
Can the elastic load balance be used with other services?
No it is used for distributing traffic to EC2 instances in a ELB group.
When using the ELB and a instance stops will ELB keep sending traffic to the failed instance?
No ELB will detect that the instance has failed and stop sending traffic.
How do a ELB detact when an instance has faild?
ELB will send pings to the instance and after a treshold of faild pings the ELB will stop sending traffic to the faild instan
Dose ELB store SSL certificates?
Yes ELB is used to store SSl certificates.
Is it best practice to put sensitive data in the tags/metadata?
No as the tags/metadata is not encrypted.
For EC2-Classic security groups is there filtering on outgoing traffic?
No.
With regard to EC2-Classic, by default has the security group got port 22(ssh) open?
Yes.
With regard to EC2-Classic, by default has the security group got ports other then 22(ssh) open?
No.
Can you monitor a EC2 instance?
You can monitor the instance from a hardware perspective.
What EC2 monitoring parameters do you get by default?
CPU, Disk Reads, Disk Writes, Disk read operations, Network in, Network out, status check failed instance, status check failed system, .
Are the EC2 monitoring parameters the host parameters or the VM OS parameters?
Host parameters.
With EC2 basic monitoring is the interval time 1min?
No the basic monitoring is 5min, this is the default monitoring.
With regard to EC2 monitoring the default interval is 5min, can you get a faster interval limit?
Yes you can have 1min.
With regard to EC2 monitoring the default interval is 5min and when you select a interval of 1min do you pay for it?
Yes you pay extra.
Is it possible to create alarms with EC2 monitoring?
Yes you can create alarms and have them monitored by CloudWatch.
Can you attach a volume in one AZ to a instance in another AZ?
No.
Can you launch a volume from a snapshot?
Yes.
How would you move a volume from one AZ to another?
Create a snapshot, create volume from image.
How would you copy a volume from one AZ region to another AZ region?
Create snapshot, copy snapshot (this will gibe you region options)
Do EBS volumes exist outside of a AZ and with in the region?
No, volumes exist with in the AZ (data centre)
How can you create a image from a snapshot?
AWS provides a create image from snapshot function.
How many 9’s availability has a EBS volume snapshot?
4 x 9s.
Where are EBS volume snapshots stored?
On AWS S3 storage.
How may 9’s durability has EBS snapshots?
11 X 9’s.
Are snapshots full or incremental snapshots?
Snapshots are incremental.
What is a provisioned IOPS EBS volume?
It is a volume where you have defined the IOPS for the volume.
With provisioned IOPS EBS volume do you pay any other charges then the storage charge?
Yes you pay for the IOP’s.
Can you attaches multiple volumes to a instance?
Yes.
What durability has a EBS volume?
Data is replicated with in a AZ to ensure again a single disk failure.
Dose amazon offer the ability to encrypt a EBS volume?
No.
Dose Ubuntu support user data ?
Yes, user data is much like cloud init and is supported by Ubuntu.
Dose amazon distro’s support user date?
Yes, user data is much like cloud init and is supported by amazon distro.
What is user date?
It is a plane bash script that is run by supported distros during start up.
What is a security group?
It is like a firewall.
When security groups with EC2-Classic can you filter outgoing traffic?
No filtering is on input traffic only.
Do instances with in the same security group require ports to be opened in the security group to enable inter instance communicate?
No instances in the same security group are free to send and receive traffic between other instances.
Can instances in two different security groups communicate with each other by default?
No, instances in separate security groups require ports to be opened in the security groups.
With regard to security groups, is it possible to allow all traffic one group to communicate with instances in another group?
Yes, you can use all t traffic and the group id instead of 0.0.0.0/0.
What types of placement groups are they?
- Clustered
- Partitioned
- Spread
I have an HPC workload, how should I deploy this with a placement group?
Clustered, keeping the instances close together for high bandwidth, low latency. This way they get a 10G non-blocking network. But they are exposed to be on the same hardware and failure can take all instances down.
What type of network is important when using clustered placement groups?
In clustered placement groups you get a 10GiB network thet is non-blocking and low latency.
Are Clustered placement groups available across AZ’s?
No, all instances have to live inside a single AZ.
If you are using provisioned IOPS, do you have to pay for them even if you do not use them?
Yes.
What is the default interval that CloudWatch will monitor at?
5min.
Is detailed CloudWatch monitoring enabled on a per instances basis?
True.
Is it AWS best practice to store secret/access keys on the AMI?
No.
With regard to EC2-Classic, can you change a instances security group with our removing the instance?
No.
With regard to EC2-Classic, how can you change the security group?
You can not, but you can boot a instance from existing AMI into the new security group.
Can a instance be a member of more then one security group?
Yes.
With regard to EC2-Instance, will the EIP become detached when the instance is stopped?
Yes
With regard to EC2-Instance, when you stop and start a instance will the EIP automatically get reattached?
No you have to manually reattach it.
Is EC2 a global, region or availability zone service?
It is a availability zone service.
When a instance is in a VPC and it is stopped and started dose it loose it’s Elastic IP?
No.
When you start and stop and instance in a VPC, will the instance lose it private iP?
?????
What is Intel’s AES-NI?
AES-NI is 7 new Intel instructions for AES.
What is Intel’s DRNG?
It is a digital random number generator in the CPU, used with encryption.