Networking

Revision as of 05:27, 19 March 2010

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 - 192.168.1.0/24
• 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.

If you need to block a host, add it to the "for" loop in charon:/usr/local/sbin/blocked_machines. This script is called from bridge_forward, so make sure to re-run it after you updated blocked_machines.

IPv4 Allocations

kabta: 131.215.172.59

• 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.
  • 76 nfs.ugcs.caltech.edu ( Failover NFS server between athena and hestia )
• 75-85: Hosted servers that will be moved
  • 78 fo.ugcs.caltech.edu - Testing IP for failover stuff
  • 80 doldnut.ugcs.caltech.edu. (owned by devteam/Jon Dama)
  • 81: afs-a.ugcs.caltech.edu: AFS database server (current zeus uses this IP)
  • 82: afsmail.ugcs.caltech.edu: AFS file server that houses mail partitions (currently failover between hermes and athena)
• 86-105: Hosted servers
  • 86 averyfs.ugcs.caltech.edu. (Owned by Avery IMSS)
  • 87 bsi-la.ugcs.caltech.edu. (owned by Bo Adler)
  • 88 lenin (owned by Dabney comptrollers)
  • 89 donut (owned by Devteam)
  • 90 metatron (owned by Matt Maurer)
  • 91 white.caltech.edu (owned by Mike White)
  • 92 philemon.gelide.org (owned by Jon Dama)
  • 93 daisy.ugcs.caltech.edu (Elizabeth Fong)
  • 94 ballroom (Ballroom dance club, )
  • 95 hiro.ugcs.caltech.edu ( Silas's machine )
  • 98 azkaban.ugcs.caltech.edu ( Owned by Eugeniu Plamadeala, username eugeniu)
  • 99 fisheye.ugcs.caltech.edu (owned by Keegan McAllister, username keegan)
  • 100 kukulza.ugcs.caltech.edu (Patrick Xia, username patrick)
  • 101 eternity.ugcs.caltech.edu (Alex Roper, username alexr)
  • 102 vitamin-s.ugcs.caltech.edu (owned by David DiCato)
  • 103 (name not known yet) ( owned by Pat Cahalan )
  • 104 (name not known yet) ( owned by Alex Rasmussen )
• 105-124: 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 (mortal)
  • 112 helen.ugcs.caltech.edu (mortal)
  • 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 (mortal)
  • 119 midas.ugcs.caltech.edu (mortal)
  • 120 medusa.ugcs.caltech.edu (mortal)
  • 121 dictys.ugcs.caltech.edu (mortal)
• 125: printer
• 126: charon
• 127: broadcast

IPv6 Allocations

• We should get some (independent of Caltech even), if at all remotely possible.