Finals Flashcards
What influenced backup and DR?
data growth compliance with regulatory laws, undesirable maintenance, downtime windows, demand for high availability and quick data processing rate
recovery operation checklist
assessing the problem, escalating it, declaration of disaster, activating and implementing the plan in DR phase
Enumerate the different backup methods
Full Backup, Incremental Backup, Differential Backup, Full Backup + Incremental Backup, Full Backup + Differential Backup, Incremental forever Backup, Synthetic Backup
What backup method?
- all files and folders are backed up
- used as an initial backup
- repeated after a set of incremental or differential backups to update the original full back-up with updates
full backup
advantages of full backup
advantages
- easy to manage
- easy to maintain
disadvantages of full backup
- takes a very long time
- consumes massive storage space
- exact same files are stored repeatedly, inefficient use of storage
all changes or newly added data since the last full backup or incremental backup are backed up; generally used after a full backup to save time
incremental backup
advantages of incremental backup
- much faster backup
- efficient use of storage space; files are not duplicated
disadvantages of incremental backup
- restores are slower
- restores are complicated; the full backup and all consecutive incremental backups are needed to perform a restore
all changes or newly added data that took place since last full or differential backup are backed up and merged into next days’ differential backup, making restoration process faster
differential backup
advantage of differential backup
- faster backups and restores
- faster backup than full backup but slower than incremental
- faster restoration than incremental backup but slower than full backup
disadvantage of differential backup
- not an efficient use of storage space; files modified after a differential backup will be duplicated again with the following differential backup
- restores are slightly complicated; full backup and last differential backup copies are needed to restore
full backup is repeated after a set of incremental backups; last full backup and incremental backups are needed to restore data
full backup + incremental backup
the full backup is repeated after a set of differential backups; the last full backup and last differential backups are needed to restore data
full backup + differential backup
all changes that take place since first full backup copy are backed up; sequential backups are conducted forever
incremental forever backup
advantage of incremental forever backup
- reduce length of backup window
- no need for scheduling the full backup
- reduces load on network
- availability of data
- transparency in restoration procedure
disadvantage of incremental forever backup
full backup + all incremental backup are needed to restore
initial full backup then incremental backups are performed; this backup is not created from original data; full backup will be merged into the following incremental backup to form a new synthetic full backup
synthetic backup
advantages of synthetic backup
- consumes less time to perform backup
- costs are reduced
- lower restore time
what are the two most important storage system technologies
file level storage and block level storage
this is the process of creating raw blocks of storage, which can be handled individually; commonly used in SAN (storage area network); it is presented as a hard disk to the server; the blocks are controlled by the server based OS
block level storage
advantages of block level storage systems
- offers better speed
- popular with SAN users
- reliable
- transport system is efficient