misc

sysctl.conf

@@ -1,21 +1,38 @@
 # /etc/sysctl.conf - Configuration file for setting system variables
 # See sysctl.conf (5) for information.
 
+# you can have the CD-ROM close when you use it, and open
+# when you are done.
 #dev.cdrom.autoeject = 1
 #dev.cdrom.autoclose = 1
 
+# protection from the SYN flood attack
 net/ipv4/tcp_syncookies=1
+
+# see the evil packets in your log files
 net/ipv4/conf/all/log_martians=1
+
+# makes you vulnerable or not :-)
 net/ipv4/conf/all/accept_redirects=0
 net/ipv4/conf/all/accept_source_route=0
 net/ipv4/icmp_echo_ignore_broadcasts =1
+
+# needed for routing, including masquerading or NAT
 #net/ipv4/ip_forward=1
+
+# sets the port range used for outgoing connections
 #net.ipv4.ip_local_port_range = 32768    61000
 
-# Broken routers will corrupt the window scaling and ECN
+# Broken routers and obsolete firewalls will corrupt the window scaling
+# and ECN. Set these values to 0 to disable window scaling and ECN.
+# This may, rarely, cause some performance loss when running high-speed
+# TCP/IP over huge distances or running TCP/IP over connections with high
+# packet loss and modern routers. This sure beats dropped connections.
 #net.ipv4.tcp_default_win_scale = 0
 #net.ipv4.tcp_ecn = 0
 
+# Swapping too much or not enough? Disks spinning up when you'd
+# rather they didn't? Tweak these.
 #vm.vfs_cache_pressure = 100
 #vm.laptop_mode = 0
 #vm.swappiness = 60
@@ -31,6 +48,7 @@ net/ipv4/icmp_echo_ignore_broadcasts =1
 #kernel.sysrq = 1
 
 # Change name of core file to start with the command name
+# so you get things like: emacs.core mozilla-bin.core X.core
 #kernel.core_pattern = %e.core
 
 # NIS/YP domain (not always equal to DNS domain)