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@HacKanCuBa
HacKanCuBa / sshd_config
Last active May 16, 2022 22:33
Modern secure SSH daemon config
# Modern secure (OpenSSH Server 7+) SSHd config by HacKan
# Refer to the manual for more info: https://www.freebsd.org/cgi/man.cgi?sshd_config(5)
# Server fingerprint
# Regenerate with: ssh-keygen -o -f /etc/ssh/ssh_host_rsa_key -N '' -t rsa -b 4096
HostKey /etc/ssh/ssh_host_rsa_key
# Regerate with: ssh-keygen -o -f /etc/ssh/ssh_host_ed25519_key -N '' -t ed25519
HostKey /etc/ssh/ssh_host_ed25519_key
# Log for audit, even users' key fingerprint
@mikejoh
mikejoh / docker-dhcpd.md
Last active June 2, 2024 16:16
Short guide on how to set up a Docker container as a DHCP server

Setting up a Docker container as a DHCP server

In this guide I’ve tested a number of different commands and configurations using Docker to run a container with dhcpd (+macvlan driver) to serve my clients in my home network. In the end i’ll migrate from my Windows 2012 R2 Server running DHCP to a much more lightweight Docker container (7.42 MB in total). Wow.

My home environment:

  • Firewall (Juniper)
    • I’m running IP helper for bootp which in this case means that i relay DHCP requests from various VLANs into one where i've placed my Windows 2012 R2 server. This is also where my container will live. See the FW configuration below:
@jboner
jboner / latency.txt
Last active July 20, 2024 23:12
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD