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| OWASP Top Ten https://owasp.org/www-project-top-ten/ | |
| The CWE Top 25 | |
| https://www.sans.org/top25-software-errors/ | |
| 2022 CWE Top 25 Most Dangerous Software Weaknesses | |
| https://cwe.mitre.org/top25/archive/2022/2022_cwe_top25.html | |
| OSSTMM 3 – The Open Source Security Testing Methodology Manual | |
| https://www.isecom.org/OSSTMM.3.pdf | |
| OWASP Web Security Testing Guide | |
| https://owasp.org/www-project-web-security-testing-guide/ |
| Network Block Device(nbd): | |
| In Linux, a network block device is a device node whose content is provided by a remote machine. Typically, network block devices are used to access a storage device that does not physically reside in the local machine but on a remote one. As an example, the local machine can access a fixed disk that is attached to another computer. | |
| 1.start nbd-server to export a qcow2 image with absolute path on the NBD server host. | |
| # nbd-server 12345 /home/my-data-disk.qcow2 | |
| 2.launch a KVM guest with this exported image as a data disk. | |
| # qemu-img info nbd:10.66.83.171:12345 | |
| image: | |
| file format: qcow2 | |
| virtual size: 10G (10737418240 bytes) |
mainly used in start-up script
When we play with iptables aka firewall we might end up in situation, where we execute rule, which has unforseen impact - lock yourself out. Recovering from this situation is necessity.
How to:
- Enable reboot via SMS.
- Test all commands in shell first before putting them into Start-up script. This way the command will be wiped out, when unit is rebooted.
Ventura docs for M2 Macs in this comment: https://gist.github.com/henrik242/65d26a7deca30bdb9828e183809690bd?permalink_comment_id=4555340#gistcomment-4555340
Old Monterey docs in this old revision: https://gist.github.com/henrik242/65d26a7deca30bdb9828e183809690bd/32c410e3a1de73539c76fa13ea5486569c4e0c5d
Solution for Sonoma: https://gist.github.com/sghiassy/a3927405cf4ffe81242f4ecb01c382ac
| # Constructed with help from | |
| # http://stackoverflow.com/questions/53497/regular-expression-that-matches-valid-ipv6-addresses | |
| # Try it on regex101: https://regex101.com/r/yVdrJQ/1 | |
| import re | |
| IPV4SEG = r'(?:25[0-5]|(?:2[0-4]|1{0,1}[0-9]){0,1}[0-9])' | |
| IPV4ADDR = r'(?:(?:' + IPV4SEG + r'\.){3,3}' + IPV4SEG + r')' | |
| IPV6SEG = r'(?:(?:[0-9a-fA-F]){1,4})' | |
| IPV6GROUPS = ( |
• 45-minute systems interview, focus on responding to real world problems with an unhealthy service, such as a web server or database. The interview will start off at a high level troubleshooting a likely scenario, dig deeper to find the cause and some possible solutions for it. The goal is to probe your knowledge of systems at scale and under load, so keep in mind the challenges of the Facebook environment.
• Focus on things such as tooling, memory management and unix process lifecycle.
More specifically, linux troubleshooting and debugging. Understanding things like memory, io, cpu, shell, memory etc. would be pretty helpful. Knowing how to actually write a unix shell would also be a good idea. What tools might you use to debug something? On another note, this interview will likely push your boundaries of what you know (and how to implement it).
Interview is all about taking an ambiguous question of how you might build a system and letting