AWS Part 3 (201-250) Flashcards
What happens when EC2 instance is halted or ended?
- Shutdown is performed typical way
- EBS volumes can stay joined and begin again
- Occurence hours are NOT charged when ceased state
deleteontermination is set to false
What are the mainstream DevOps devices?
6 devices mentioned - J. G. N. S. D. PCA.
- Jenkins ~ Continuous Integration tool
- Git ~ Version Control System tool
- Nagios ~ Continuous Monitoring tool
- Selenium ~ Continuous Testing tool
- Docker ~ Containerization tool
- Puppet, Chef, Ansible ~ Deployment & Configuration Admin tools
What are IAM Roles and Policies? What is difference between IAM Roles, and Policies?
Roles: for AWS Services, assign permissions of some AWS service to another service
- Example - Give S3 permission to EC2 to access buckets
Policies: for users and groups, assign perimmissions to users and groups
- Example - Give permission to user to access S3 buckets
What are the default services we get when we create AWS VPC?
3 main services offered… R. N. S.
- Route Table
- Network ACL (NACL)
- Security Group
What is difference between Public Subnet and Private Subnet?
Public: will have IGW attached to route table, private will NOT have IGW attached
Causing no internet for private subnet…
How do you access EC2 with Private IP in a Private Subnet?
Using VPN, if configured to that VPC
Can access using other EC2 with public access
We have custom VPC configured and MySQL DB server which is on Private Subnet. Need to update MySQL DB server, what are the options to do so?
Using NAT Gateway in the VPC
. or Launch NAT instance EC2 config
. or Attach NAT Gateway in Public Subnet and attach it to the Route Table
What is the difference between Security Groups and NACLs?
4 main things - Attached to ? Stateful or Stateless? Block IP? Rules?
Security Groups:
- Attached to EC2 instance
- Stateful for incoming/outgoing rules
- Blocking IP address can’t be done
- Allow rules only, by default rules are denied
NACL:
- Attached to Subnet
- Stateless - Incoming rules only
- IP address can be blocked
- Allow and Deny can be used
What are differences between Route53 and ELB?
Route53 handles DNS servers with web interface
Elastic Load Balancing auto scales depending on the demand
Which engines can be used in AWS RDS?
5 main engines mentioned here
- MariaDB
- MySQL DB
- MS SQL DB
- Postgre DB
- Oracle DB
What are Status Checks in EC2?
Can you list 9 types of check?
Look for issues with instances for the following:
1. Network
2. Power
3. Software
4. Hardware
5. Instance
6. Memory
7. Files
8. Kernels
9. Failed checks
To establish peering between 2 VPC’s, what conditions must be met?
Discuss about CIDR and locations
- CIDR block should NOT overlap between VPC settings for peering.
- Peering connection is allowed within a region, across region, across different accounts
Troubleshoot with EC2 instances
2 examples and 2 potential solutions
- If instance state is (0/2) then there may be hardware issue
- If instance state is (1/2) then there may be issue with OS
Workaround - Restart, or if no resolutio then check logs
How can EC2 instances be resized?
Can scale UP or DOWN based on requirement
What is EBS?
Block-level storage volume which can be used after mounting EC2 instances
Difference between EBS, EFS, and S3?
EBS: Can be accessed ONLY after is mounted with instance
EFS: Can be shared with multiple instances
S3: Can be access without mounting with instances
Max number of buckets that can be created in AWS?
You can creat up to 100 buckets per AWS account
Max number of EC2 instances that can be created in VPC?
You can create up to 20 reserved instances and request Spot as per demand
How can EBS be accessed?
After mounting to EC2 instance, it can be accessed
What is process to mount EBS to EC2 instance?
Coding ahead:
- Df-k
- mkfs.ext4/dev/xvdf
- Fdisk -|
- Mkdir /my5gbdata
- Mount /dev/xvdf /my5gbdata