- Tech Support Notes
- introduction
- 1. Topic 01: Firewalls
- 2. Topic 02: Package Management
- 3. Topic 03: Networking
- 4. Topic 04: DNS
- 5. Topic 5: Configuration Files
- 6. Topic 6: Mysql
- 7. Topic 7: Apache
- 8. Topic 8: Memory
- 9. Topic 9: Process Tracking
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10.
Topic 10: Partitions/Filesystems
- 10.1. Basic Layout
- 10.2. creating / modifying
- 10.3. fdisk / parted
- 10.4. fstab / mount
- 10.5. labels / uuid
- 10.6. LVM Part One
- 10.7. LVM Part Two
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11.
Topic 11: Devices/shares
- 11.1. samba / nfs / nas
- 11.2. iscsi
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12.
Topic 12: Space and drive usage
- 12.1. du / df / inodes
- 12.2. iostat
- 12.3. smartctl
- 13. Topic 13: Logging
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14.
Topic 14: Finding Exploits
- 14.1. maldet
- 14.2. rootkit hunter
- 14.3. windows
- 15. Topic 15: Email
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16.
Topic 16: Find
- 16.1. find examples
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17.
Topic 17: Rescue Layer/Live Environment
- 17.1. mounting filesystem / chroot
- 17.2. cloning
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18.
Topic 18: Permissions/users/groups
- 18.1. permissions
- 18.2. users
- 18.3. groups
- 19. Topic 19: Cpanel
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20.
Topic 20: Plesk
- 20.1. general
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21.
Topic 21: Windows
- 21.1. windows to sort
- 21.2. hyper-v
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22.
Topic 22: Freebsd
- 22.1. installing packages
- 22.2. networking
- 22.3. drive management
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23.
Topic 23: Dumping ground
- 23.1. sed / awk
- 23.2. gdb
- 23.3. curl / wget
- 23.4. compress / uncompress
- 23.5. rsync / scp
- 23.6. Random commands
Topic 1: Firewalls
This section is related to the most common software firewalls that you will encounter while doing system administration/technical support.
Here are some additional utilities for blocking/securing traffic that are not mentioned in this Topic:
Fail2ban - Fail2ban scans log files (e.g. /var/log/apache/error_log) and bans IPs that show the malicious signs -- too many password failures, seeking for exploits, etc.
Pf - Packet Filter (Referred to as PF) is OpenBSD's system for filtering TCP/IP traffic and doing Network Address Translation