TCP/IP Networking

• Network Configuration
  • manual
    • Documentation is at RedHat Install Guide section 11.9.1 page 162
    • /etc/sysconfig/network
      • File is sourced, These are just environment variables
        • NETWORKING=
          • yes
          • no
        • HOSTNAME=
          • or /etc/hostname
        • FORWARD_IPV4=
          • yes
          • no -- default
        • NISDOMAIN=<nisdomainname>
        • GATEWAY=<gw-ip>
        • GATEWAYDEV=<gateway device> like eth0
    • /etc/sysconfig/network-scripts
      • RedHat Install Guide page 164
      • ifup <interface> is run in /etc/rc.d/init.d/network
      • ifcfg-<interface>
        • DEVICE=<interface>
        • IPADDR=<ip address>
        • NETMASK=<netmask>
        • BROADCAST=<broadcast>
        • NETWORK=<network>
        • ONBOOT
          • yes
          • no
        • BOOTPROTO
          • none
          • bootp
          • dhcp
        • USERCTL
          • yes
          • no
  • netcfg (X based)
    • start via control panel
    • start from command line -- netcfg
    • Documentation is in RedHat Install Guide section 9.4 page 125
• Host Name resolution
  • /etc/nsswitch
  • /etc/hosts
  • /etc/resolv.conf
  • /etc/hosts.conf -- old way
• Network Customization
  • /etc/inetd.conf
    • Same as other vendors
    • Comment out items not needed
    • uses tcp wrappers by default
      • Need to tighten up
  • sendmail
    • comes with anti-spam rules
  • Apache
    • Please do not Run unless you actually configure it. Need to register yourself with Computing Division Web group
  • Samba
    • Not supported at this time
  • Time Sync
    • xntp
  • PPP
  • NFS
  • NIS
• Debugging tools
  • ping
  • traceroute
  • ifconfig
  • route
    • used to set routes
    • used to get routes vs netstat -r
  • netstat
• ipfwadm