useful systems
- http reverse proxies / load balancers
- nginx
- HAProxy
- message queuing
passwords
If you have an open system and base password checks on hashes then it's may be an issue that somebody can guess a password by just trying to find a word that will produce the same hash as for somebody else. So the security also is based on how long it takes to do a brood force attach on such hashes.
- And so it might be helpful to know that do a hash in python with sha1 you can calculate about 50000 more hashes of passwords then with bcrypt.*
(see here at around 16:30)
DB
dd command with progress
- start the dd command as intended
- open another shell
- find dd command process id (e.g. via pgrep -l '^dd$')
- send USR1 signal via kill -USR1 <processID>
- or send it regularly via watch -n 10 kill -USR1 <processID>