Routing Hackers To /dev/null (Blackhole)

Add: route add -host attacker_ip 127.0.0.1 -blackhole Remove: route delete -host attacker_ip 127.0.0.1 -blackhole The above will route all traffic from the “attacker_ip” to a blackhole. This is useful when you see someone relentlessly attacking any daemon on your server (ssh, http, ftp, etc). [ad#Google Adsense]

Decrypt SMIME E-Mails – BlackBerry/iPhone

I, and most everyone I deal with, use SMIME e-mail certificates from Verisign/Thawte/Home Brew. Unfortunately, these e-mails can not be viewed on an BlackBerry (without BES) or iPhone. I overcame this by creating an alias on my server that would receive e-mails, decrypt them, and send them back to me -> UNENCRYPTED. [NOTE: If you ...

FreeBSD: Aliasing IPs

[ad#Google Adsense] Edit /etc/rc.conf The primary IP of the machine will be defined by a line that looks similar to this: ifconfig_rl0=”inet 192.168.1.2 netmask 255.255.255.0″ To add additional IPs you simply: ifconfig_rl0_alias0=”inet 192.168.1.3 netmask 255.255.255.255″ ifconfig_rl0_alias1=”inet 192.168.1.4 netmask 255.255.255.255″ [ad#Google Adsense]

FreeBSD: Moving To A Larger Harddrive

[ad#Google Adsense] Moving to a Larger Hard Drive Applicable to: FreeBSD 4.3 and Higher This Sheet describes the procedure I used to move my company’s FreeBSD system to a larger hard drive. 1. Verify that the system supports two hard drives. If not, rebuild the kernel with support for two hard drives: # ATA and ...

Resume SCP / SSH Downloads

Works most of the time: rsync –archive -partial -progress –rsh=ssh

Networking Subnets – Quick Reference

[ad#Google Adsense] notation resulting subnet netmask shorthand number of addresses 255.255.255.0 /24 [8-bit] 28 = 256 = 254 hosts + 1 bcast + 1 net base 255.255.255.128 /25 [7-bit] 27 = 128 = 126 hosts + 1 bcast + 1 net base 255.255.255.192 /26 [6-bit] 26 = 64 = 62 hosts + 1 bcast + ...