- EBS are placed in a specific AZ, where they are automatically replicated. (Not to different AZ, but between SANs)
- cannot mount to multiple instances
- EC2 and EBS volume have to be in the same AZ
- can't modify standard volume, can change volume size and storage type on the fly
- Magentic standard (bootable)
- GP2
- IO1
- GP2, general purpose SSD
- 3 IOPS per GB with up to 10k IOPS, burst up to 3k IOPS
- Provisioned IOPS SSD (IO1)
- I/O intensive
- if you need >10k IOPS
- provision up to 20k IOPS
- Throughput optimized HDD (ST1)
- big data
- data warehouses
- Log processing
- sequential data
- cannot be a boot volume
- Cold HDD (SC1)
- low cost
- file server
- cannot be a boot volume
- Magnetic (Standard)
- bootable
- lowest cost
I/O Credits
when required more than the baseline performance I/O, EBS will use I/O credits to burst performance level, up to 3k IOPS
- 5400000 I/O credits initially
- enough for 3k IOPS for 30 minuntes
- earn credits when not going over provisioned IO level
- snapshots exist on S3
- snapshots are point in time copies of volumes
- snapshots are incremental
- you can create AMIs from volumes and snapshots
- to move EC2 volume from one AZ/region to another - take a snap or an image, then copy it to the new region
- snaps of encrypted volumes are encrypted automatically
- volumes restored from encrypted snapshots are encrypted automatically
- you can share snapshots, but only unecrypted
- snap can be shared with other AWS accounts or made public
- snapshot for root EBS volumes -> stop the instance before taking the snapshot
- Ephemeral storage
- can't stop. If the underlying host fails - will lose data
- EBS backed can be stopped
- Can reboot both
Restoring volumes from snapshots -> read all block from volume before using -> pre-warming
- Read|Write Byets
- Read|Write Ops
- Total Read|Write Time
- IdeTime
- QueueLength - number of IO waiting to be completed
- ThroughputPercentage
- ConsumedReadWriteOps
- ok
- warning
(severely) degraded, but available
- impaired (stalled/not available)
volume offline/pending recovery, or waiting for the user to enable I/O
- insufficient-data
- online size change
- change volume type or adjust IOPS performance