The Hello GPE World Tutorial

Pinging SPP External Interfaces

Unlike most PlanetLab nodes, an SPP has multiple external interfaces. In the GENI deployment, some of those interfaces have Internet2 IP addresses and some are interfaces attached to point-to-point links going directly to an external interfaces of other SPPs. This section introduces you to sone of the Internet2 interfaces.

Let's try to ping some of those Internet2 interfaces. Enter one of the following ping commands (omit the comments):

    ping -c 3 64.57.23.194         # Washington DC interface 0
    ping -c 3 64.57.23.198         # Washington DC interface 1
    ping -c 3 64.57.23.202         # Washington DC interface 2
    ping -c 3 64.57.23.178         # Salt Lake City interface 0
    ping -c 3 64.57.23.182         # Salt Lake City interface 1
    ping -c 3 64.57.23.186         # Salt Lake City interface 2
    ping -c 3 64.57.23.210         # Kansas City interface 0
    ping -c 3 64.57.23.214         # Kansas City interface 1
    ping -c 3 64.57.23.218         # Kansas City interface 2

For example, my output from the first ping command looks like this:

myhost> ping -c 3 64.57.23.194
PING 64.57.23.178 (64.57.23.178) 56(84) bytes of data.
64 bytes from 64.57.23.178: icmp_seq=1 ttl=56 time=67.5 ms
64 bytes from 64.57.23.178: icmp_seq=2 ttl=56 time=55.9 ms
64 bytes from 64.57.23.178: icmp_seq=3 ttl=56 time=59.0 ms

--- 64.57.23.178 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2002ms
rtt min/avg/max/mdev = 55.949/60.823/67.511/4.895 ms

Note that you may not be able to ping an SPP external interface. Some reasons why you may fail are:

1. Your host doesn't have ping installed. This is not typical.
2. The SPP interface or the SPP is down.
3. Your network adminstrator blocks ping traffic.
4. Your network provider doesn't route Internet2 addresses.

In the first case, you will get a command not found error message. In the other casex, your ping command will eventually return with a 100% packet loss message. In the last case, running traceroute 64.57.23.178 may give a Network unreachable indication (the last router is marked !N).

However, you can always get around this if you can log into a PlanetLab node, and enter the ping command from there. We discuss how to log into a PlanetLab node in The IPv4 Metanet Tutorial.

Logging Into a SPP's GPE

>>>>> HERE <<<<<

Getting Information About Interfaces and Peers

• The scfg utility
• scfg --cmd get_ifaces
• scfg --cmd get_peer

Constructing a Tunnel Map

• Use the output of get_ifaces and get_peer

Making a Resource Reservation

• scfg --cmd make_reservation and the reservation file
• Other reservation commands

Creating a Slowpath (GPE) Endpoint

• scfg --cmd alloc_plspec
• scfg --cmd alloc_endpoint