(Boeing r1765)

added simple distributed Python script example involving N/2 local nodes and
 N/2 nodes on a remote server, connected to a common switch

lacks runtime access to the remote nodes (e.g. for command execution)

daemon/examples/netns/distributed.py

@@ -0,0 +1,146 @@
+#!/usr/bin/python -i
+
+# Copyright (c)2010-2013 the Boeing Company.
+# See the LICENSE file included in this distribution.
+
+# A distributed example where CORE API messaging is used to create a session
+# distributed across the local server and one slave server. The slave server
+# must be specified using the '-s <ip address>' parameter, and needs to be
+# running the daemon with listenaddr=0.0.0.0 in the core.conf file.
+#
+
+import sys, datetime, optparse, time
+
+from core import pycore
+from core.misc import ipaddr
+from core.constants import *
+from core.api import coreapi
+
+# declare classes for use with Broker
+coreapi.add_node_class("CORE_NODE_DEF", 
+                       coreapi.CORE_NODE_DEF, pycore.nodes.CoreNode)
+coreapi.add_node_class("CORE_NODE_SWITCH",
+                       coreapi.CORE_NODE_SWITCH, pycore.nodes.SwitchNode)
+
+# node list (count from 1)
+n = [None]
+
+def add_to_server(session):
+    ''' Add this session to the server's list if this script is executed from
+    the core-daemon server.
+    '''
+    global server
+    try:
+        server.addsession(session)
+        return True
+    except NameError:
+        return False
+
+def main():
+    usagestr = "usage: %prog [-h] [options] [args]"
+    parser = optparse.OptionParser(usage = usagestr)
+    parser.set_defaults(numnodes = 5, slave = None)
+
+    parser.add_option("-n", "--numnodes", dest = "numnodes", type = int,
+                      help = "number of nodes")
+    parser.add_option("-s", "--slave-server", dest = "slave", type = str,
+                      help = "slave server IP address")
+
+    def usage(msg = None, err = 0):
+        sys.stdout.write("\n")
+        if msg:
+            sys.stdout.write(msg + "\n\n")
+        parser.print_help()
+        sys.exit(err)
+
+    # parse command line options
+    (options, args) = parser.parse_args()
+
+    if options.numnodes < 1:
+        usage("invalid number of nodes: %s" % options.numnodes)
+    if not options.slave:
+        usage("slave server IP address (-s) is a required argument")
+
+    for a in args:
+        sys.stderr.write("ignoring command line argument: '%s'\n" % a)
+
+    start = datetime.datetime.now()
+
+    prefix = ipaddr.IPv4Prefix("10.83.0.0/16")
+    session = pycore.Session(persistent=True)
+    add_to_server(session)
+
+    # distributed setup - connect to slave server
+    slaveport = options.slave.split(':')
+    slave = slaveport[0]
+    if len(slaveport) > 1:
+        port = slaveport[1]
+    else:
+        port = coreapi.CORE_API_PORT
+    print "connecting to slave at %s:%d" % (slave, port)
+    session.broker.addserver(slave, slave, port)
+    session.broker.setupserver(slave)
+    session.setstate(coreapi.CORE_EVENT_CONFIGURATION_STATE)
+    tlvdata = coreapi.CoreEventTlv.pack(coreapi.CORE_TLV_EVENT_TYPE,
+                                        coreapi.CORE_EVENT_CONFIGURATION_STATE)
+    session.broker.handlerawmsg(coreapi.CoreEventMessage.pack(0, tlvdata))
+
+    switch = session.addobj(cls = pycore.nodes.SwitchNode, name = "switch")
+    switch.setposition(x=80,y=50)
+    num_local = options.numnodes / 2
+    num_remote = options.numnodes / 2 +  options.numnodes % 2
+    print "creating %d (%d local / %d remote) nodes with addresses from %s" % \
+          (options.numnodes, num_local, num_remote, prefix)
+    for i in xrange(1, num_local + 1):
+        tmp = session.addobj(cls = pycore.nodes.CoreNode, name = "n%d" % i,
+                             objid=i)
+        tmp.newnetif(switch, ["%s/%s" % (prefix.addr(i), prefix.prefixlen)])
+        tmp.cmd([SYSCTL_BIN, "net.ipv4.icmp_echo_ignore_broadcasts=0"])
+        tmp.setposition(x=150*i,y=150)
+        n.append(tmp)
+
+    flags = coreapi.CORE_API_ADD_FLAG
+    session.broker.handlerawmsg(switch.tonodemsg(flags=flags))
+
+    # create remote nodes via API
+    for i in xrange(num_local + 1, options.numnodes + 1):
+        tmp = pycore.nodes.CoreNode(session = session, objid = i,
+                                    name = "n%d" % i, start=False)
+        tmp.setposition(x=150*i,y=150)
+        tmp.server = slave
+        session.broker.handlerawmsg(tmp.tonodemsg(flags=flags))
+
+    # create remote links via API
+    for i in xrange(num_local + 1, options.numnodes + 1):
+        tlvdata = coreapi.CoreLinkTlv.pack(coreapi.CORE_TLV_LINK_N1NUMBER,
+                                           switch.objid)
+        tlvdata += coreapi.CoreLinkTlv.pack(coreapi.CORE_TLV_LINK_N2NUMBER, i)
+        tlvdata += coreapi.CoreLinkTlv.pack(coreapi.CORE_TLV_LINK_TYPE,
+                                            coreapi.CORE_LINK_WIRED)
+        tlvdata += coreapi.CoreLinkTlv.pack(coreapi.CORE_TLV_LINK_IF2NUM, 0)
+        tlvdata += coreapi.CoreLinkTlv.pack(coreapi.CORE_TLV_LINK_IF2IP4,
+                                            prefix.addr(i))
+        tlvdata += coreapi.CoreLinkTlv.pack(coreapi.CORE_TLV_LINK_IF2IP4MASK,
+                                            prefix.prefixlen)
+        msg = coreapi.CoreLinkMessage.pack(flags, tlvdata)
+        session.broker.handlerawmsg(msg)
+
+    session.instantiate()
+    tlvdata = coreapi.CoreEventTlv.pack(coreapi.CORE_TLV_EVENT_TYPE,
+                                        coreapi.CORE_EVENT_INSTANTIATION_STATE)
+    msg = coreapi.CoreEventMessage.pack(0, tlvdata)
+    session.broker.handlerawmsg(msg)
+
+    # start a shell on node 1
+    n[1].term("bash")
+
+    # TODO: access to remote nodes is currently limited in this script
+
+    print "elapsed time: %s" % (datetime.datetime.now() - start)
+
+    print "To stop this session, use the 'core-cleanup' script on this server"
+    print "and on the remote slave server."
+
+if __name__ == "__main__" or __name__ == "__builtin__":
+    main()
+

packaging/rpm/core.spec.in

@@ -249,6 +249,7 @@ sed -i 's/emane_realtime = True/emane_realtime = False/' /etc/core/core.conf
 %{_datadir}/%{name}/examples/myservices/README.txt
 %{_datadir}/%{name}/examples/myservices/sample.py*
 %{_datadir}/%{name}/examples/netns/basicrange.py*
+%{_datadir}/%{name}/examples/netns/distributed.py*
 %{_datadir}/%{name}/examples/netns/emane80211.py*
 %{_datadir}/%{name}/examples/netns/howmanynodes.py*
 %{_datadir}/%{name}/examples/netns/iperf-performance-chain.py*