Networking

Please, do not fill this up with our speculation from Planning. This table is meant for hard current IPs and final IPs and other network configuration relevant to the current status of the build.

Contents 1 Static IPs in UGCS 2 VLANs 3 Network Security 4 IP Allocations

Static IPs in UGCS

Within UGCS, we get only part of the subnet, and the gateway isn't in that part. As a result, the following wonky config snippet is recommended by Maurer (and Liz, the bridging will work fine with this config). Note the MTU - because we use VLANs, we have 4 less bytes to work with.

 allow-hotplug eth0
 iface eth0 inet static
 address 131.215.176.num
 broadcast 131.215.176.127
 netmask 255.255.255.192
 mtu 1496
 # Route the Gateway
 post-up route add 131.215.176.254 eth0
 post-up route add default gw 131.215.176.254

VLANs

• Vlan 1: default (outside world/ITS) - 131.215.176.0/26 131.215.176.128/25
• Vlan 2: management - 192.168.0.0/24
• Vlan 3: core servers - 131.215.176.65-131.215.176.85
• Vlan 4: shell servers - 131.215.176.96-131.215.176.125
• Vlan 5: hosted servers - 131.215.176.86-131.215.176.95

All Vlans except for management fall within the same basic subnet; traffic can be routed without use of a gateway and thus subnetting is not required. However, traffic is passed between Vlans by a transparent bridge which performs packet filtering using IPTables and Snort in order to segregate traffic (for example, not allowing DHCP server responses to cross from Vlan 1 to inside or outward from Vlans 3-5 to Vlan 1). There is no access to Vlan2 except from the bridge itself. The bridge has IP 131.215.176.126

All servers must be registered with the bridge in order to receive a UGCS-internal Vlan assignment using VMPS and therefore a DHCP allocation from the UGCS DNS server; otherwise, they will be on Vlan 1 and be on the main Winnett network and get a DHCP address from the Winnett pool.

Network Security

Charon bridges the VLAN's, so any traffic that flows across a vlan barrier is subject to firewall rules. By default, coreserver ports are filtered, and shellserver ports are open.

Charon also runs snort, but nothing is done with the alerts yet. Its rules are auto-updated daily from bleedingthreats.net.

IP Allocations

• 64: Netblock
• 65-75: Coreserver
  • 64 netblock.ugcs.caltech.edu.
  • 65 hermes.ugcs.caltech.edu.
  • 66 demeter.ugcs.caltech.edu.
  • 67 apollo.ugcs.caltech.edu.
  • 68 athena.ugcs.caltech.edu.
  • 69 persephone.ugcs.caltech.edu
  • 70 hera.ugcs.caltech.edu.
  • 71 poseidon.ugcs.caltech.edu.
  • 72 zeus.ugcs.caltech.edu.
  • 73 hestia.ugcs.caltech.edu.
  • 74 hephaestus.ugcs.caltech.edu.
  • 75 dionysus.ugcs.caltech.edu.

• 75-85: Hosted servers that will be moved
  • 77 salamander.ugcs.caltech.edu. (DNS for salamander.caltech.edu points to UGCS-176-77.caltech.edu)
  • 79 lenin.ugcs.caltech.edu.
  • 80 doldnut.ugcs.caltech.edu.
  • 81 clubs.ugcs.caltech.edu. (not in use anymore)

• 86-95: Hosted servers
  • 86 averyfs.ugcs.caltech.edu.
  • 87 bsi-la.ugcs.caltech.edu.
  • 88 New lenin
  • 89 donut
  • 90 New salamander
  • 91 white.caltech.edu
  • 92 philemon.gelide.org
  • 93 daisy.ugcs.caltech.edu (Elizabeth Fong)
  • 94 Jay Conrod's machine
  • 95 Silas's machine (hiro.ugcs.caltech.edu)
• 96-124: Shellserver
  • 105 lara.ugcs.caltech.edu.
  • 106 styx.ugcs.caltech.edu.
  • 107 minthe.ugcs.caltech.edu.
  • 108 lethe.ugcs.caltech.edu.
  • 109 calliope.ugcs.caltech.edu.
  • 110 clio.ugcs.caltech.edu.
  • 111 achilles.ugcs.caltech.edu
  • 112 helen.ugcs.caltech.edu
  • 113 melpomene.ugcs.caltech.edu.
  • 114 polyhymnia.ugcs.caltech.edu.
  • 115 terpsichore.ugcs.caltech.edu.
  • 116 thalia.ugcs.caltech.edu.
  • 117 urania.ugcs.caltech.edu.
  • 118 jason.ugcs.caltech.edu
• 125: printer
• 126: charon
• 127: broadcast