config/etc/sysctl.conf

   1 net.ipv4.ip_forward = 1
   2 net.ipv4.ip_dynaddr = 1
   3
   4 net.ipv4.icmp_echo_ignore_broadcasts = 1
   5 net.ipv4.icmp_ignore_bogus_error_responses = 1
   6 net.ipv4.icmp_ratelimit = 1000
   7 net.ipv4.icmp_ratemask = 6168
   8
   9 net.ipv4.tcp_syncookies = 1
  10 net.ipv4.tcp_fin_timeout = 30
  11 net.ipv4.tcp_syn_retries = 3
  12 net.ipv4.tcp_synack_retries = 3
  13
  14 net.ipv4.conf.default.arp_filter = 1
  15 net.ipv4.conf.default.rp_filter = 0
  16 net.ipv4.conf.default.accept_redirects = 0
  17 net.ipv4.conf.default.accept_source_route = 0
  18 net.ipv4.conf.default.log_martians = 1
  19
  20 net.ipv4.conf.all.arp_filter = 1
  21 net.ipv4.conf.all.rp_filter = 0
  22 net.ipv4.conf.all.accept_redirects = 0
  23 net.ipv4.conf.all.accept_source_route = 0
  24 net.ipv4.conf.all.log_martians = 1
  25
  26 kernel.printk = 1 4 1 7
  27 vm.swappiness=0
  28 vm.mmap_min_addr = 4096
  29 vm.min_free_kbytes = 8192
  30
  31 # Disable IPv6 by default.
  32 net.ipv6.conf.all.disable_ipv6 = 1
  33 net.ipv6.conf.default.disable_ipv6 = 1
  34
  35 # Enable netfilter accounting
  36 net.netfilter.nf_conntrack_acct=1