Flashcards in Deck 2 Deck (31)
Difference between physical RDS replication and logical
Logical is software based and physical is block based
RDS types that use physical replication
MySQL, Oracle, & Postgres
RDS instance type that use logical replication
MSSQL (server native mirroring)
What mechanism provides the failover for RDS HA?
DNS, your clients always use an endpoint
How can you force failover on an RDS instance?
Reboot the instance
How can you reboot a RDS instance?
webUI or the RebootDBInstance
How many read replicas can you have of Postgres and MySQL?
What will happen if you create a read replica of a DB that does not have multi-AZ enabled?
Brief IO pause during the snapshot
What RDS database can have read replica of read replicas?
Can you take snapshots or backup from RDS read replicas?
What Cloudwatch metric indicates the amount of time in seconds that the read replica is behind the source database
ReplicaLag. Bad lag can also indicate performance issues.
What might you have to do if you are unable to create read replicas RDS?
Edit and enable backups
What are the two ways you can monitor RDS
Metrics and Events
Which RDS Metric indicates the number of outstanding I/O requests (read and write) waiting to access the disk.
Which RDS Metric indicates the number of database connections in use.
RDS metrics that tells you how much disk space is available in Bytes
Which RDS metrics that shows the average number of disk I/O operations per second for reads and the other for writes
How ofter is an ELB monitored
Every 60 seconds unless there is no traffic
ELB metric the is a count of the total # of requests pending submission
ELB metric that would show the # of requests being rejected due to a full queue
Reasons for instance start failures on an autoscaling config
Key pairs deleted, config not working correctly, autoscaling group not found, instance type not supported, the AZ is no longer supported, Invalid EBS mapping, autoscaling not enabled on your (older) account, attempting to attach EBS to an instance store.
AWS service that allow root access
Elastic Map Reduce
When is a health check error triggered
error = interval x threshold
How does a an ELB balance sessions by default?
Based on load
ELB sticky sessions is also known as what?
Difference between ELB Duration Based sticky states and Application Based
Duration based is a cookie provided by the ELB and the expiration is based on the load balance algorithm. Application based are special cookies used to assign the session back to the original session.
How to pre-warm an ELB
You must contact Amazon and provide start and end datas, expected request rate per second, and total size of request/response rate that you are expecting
AWS is responsible for the security on which services?
DynamoDB, RDS, Redshift, Elastic Mapreduce, Workspaces
Trusted advisor currently only inspects which service