327 lines
12 KiB
Plaintext
327 lines
12 KiB
Plaintext
Id: README-3.8.mrouted,v 3.8 1995/11/29 22:23:02 fenner Rel
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IP Multicast Extensions for BSD-Derived Unix Systems
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Release 3.8
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November 29, 1995
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available from parcftp.xerox.com,
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file pub/net-research/ipmulti/mrouted3.8.tar.Z
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binaries pub/net-research/ipmulti/mrouted3.8-sparc-sunos41x.tar.Z
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pub/net-research/ipmulti/mrouted3.8-sparc-solaris2.tar.Z
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pub/net-research/ipmulti/mrouted3.8-i386-bsd.tar.Z
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pub/net-research/ipmulti/mrouted3.8-alpha-osf1.tar.Z
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pub/net-research/ipmulti/mrouted3.8-sgi-irix.tar.Z
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pub/net-research/ipmulti/mrouted3.8-hp-hpux.tar.Z
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Note: The 3.8 release is mrouted-only, and will run on top of a 3.5 kernel.
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It is a drop-in replacement for mrouted 3.5, 3.6 or 3.7 .
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The 3.8 release fixes the following bugs:
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o mrouted would fail to forget prunes when a neighbor went away,
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thus potentially sending traffic down a tunnel after the tunnel
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endpoint has gone down. This was due to some research code making
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it into the "emergency" 3.7 release, sigh.
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o mrouted could send prunes with negative lifetimes. This causes
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slightly higher prune traffic but shouldn't be any major problem.
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===========
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Release 3.7
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November 28, 1995
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The 3.7 release fixes the following bugs:
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o mrouted now ignores route reports that include bogus netmasks.
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There was a bug in 3.5 that would mangle default routes into
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tens of bogus routes; this should prevent that bug from killing
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the MBONE.
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This solution can cause route flaps and black holes until the
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3.5's are gone or all of the 3.5's neighbors are 3.7 .
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o mrouted now ignores duplicate routes. Ciscos and the above 3.5
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bug could cause two copies of the same route to appear in a single
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routing update; mrouted would insert two copies of the same route
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into its routing table and wreak all sorts of havoc.
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o mrouted now sends a group-specific query for both retransmissions
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of a g-s query; previous versions sent a general query the second
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time.
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o mrouted now loops back multicasted mtrace responses and
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group-specific membership queries
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o mrouted now performs deterministic tiebreaking between two
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neighbors on the same vif.
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o mrouted now only does duplicate suppression on traceroute requests,
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not all traceroute packets, so that a loop can be nicely detected
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via a duplicate router instead of just a timeout.
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o the buffer size that mrouted uses has been increased to allow
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more than 16 hops in mtrace messages.
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o mtrace's hop-by-hop termination is now more likely to be correct.
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o mrinfo now waits for the responses to its retransmitted queries.
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The 3.7 release has the following new features:
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o The configuration file can accept a hostname as the other end
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of a tunnel. There must be a single name->ip mapping for the
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given name, however, or mrouted will fail to start up.
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o mrinfo now sends requests to all interfaces of a multihomed host.
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o mtrace's passive mode has been implemented.
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o The first screen of mtrace statistics is shorter and more likely
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to fit on one screen.
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===========
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Release 3.6
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June 26, 1995
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The 3.6 release fixes the following bugs:
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o mrouted would dump core when attempting to report no routes (i.e. upon
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startup, if you have no enabled phyint's)
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o mrouted would dump core if requested to traceroute a source for which it
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had no route
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o neighbor flags were not always properly updated on probe or report
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o mrouted would sometimes reply to a multicast traceroute on a disabled
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phyint; now it uses the first configured phyint to reply to traceroutes.
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o host routes (i.e. netmask 0xffffffff) works now; it was discarding
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IGMP from the host because it was coming from the "broadcast address"
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of the subnet.
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o send_igmp() now treats the failure to send an mtrace or a neighbor
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reply as informational, as opposed to warning.
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o mrouted would go into an infinite loop trying to respond to a traceroute
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for a source with a netmask of 0xffffffff.
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o vifs_with_neighbors was not being reset if the mrouted was restarted
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with SIGHUP
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o the default route was not being properly advertised to neighbors (although
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it was accepted if it was advertised to it)
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o ANSI-fication for those who it helps, still-K&R-ish for those it doesn't.
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o mtrace now attempts to trace three hops past a non-responding router,
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in the hopes that it does support traceroute but just couldn't respond
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(i.e. unicast didn't work and it can't source multicast because all its
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phyints are disabled).
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o mrinfo now times out even on a multicast router.
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===========
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Release 3.5
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May 8, 1995
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The 3.5 release has the following new features:
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o The kernel and mrouted make sure that each is the correct version, to
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prevent problems with mismatched kernel/mrouted versions. A too-old
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mrouted will die with the error:
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can't enable DVMRP routing in kernel: Option not supported by protocol
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o mrouted can accept and propogate a default route (essential for
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heirarchical multicast routing)
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o Kernel route cache keeps source-specific routes instead of subnet routes,
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eliminating hashing and longest-match problems.
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(allows classless routing, longest-match and default routing)
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o Cached kernel routes only get deleted if no traffic is flowing, to
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facilitate multicast traceroute
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o mrouted has a new configuration file parser, which provides better error
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messages than before, and allows named boundaries (see man page)
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o added "netmask" to phyint configuration, at the suggestion of
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Anders Klemets
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o System V and FreeBSD compatibility from John Brezak <brezak@ch.hp.com>
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o phyint's can have additional subnets configured, for people with
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multiple subnets on one physical network. mrouted.conf syntax is
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altnet 1.2.3.0, or altnet 1.2.3.0/24 if you need to specify
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a different netmask. There can be as many altnet statements
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as you need.
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o both mrouted and the kernel now support classless addresses.
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o the kernel supports PIM assert processing by notifying the router
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when a packet arrives on the wrong interface
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o the kernel keeps additional counters, and mrouted can be compiled to
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support SNMP and the Multicast MIB
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o the packet classifier in the kernel now uses the following udp port
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ranges:
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[0, 16384) - lowest priority, unclassified
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[16384, 32768) - highest priority, i.e. audio
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[32768, 49152) - medium priority, i.e. whiteboard
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[49152, 65536) - low priority, i.e. video
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A future release of a session directory will allocate ports in these
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ranges.
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o the configuration code has been modified to default tunnels' rate_limit
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parameters to 500kbps. This is easily modified with a rate_limit keyword
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in mrouted.conf, but should be a good default for the MBONE in general.
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o The tunnel sending code now caches a route for ip_output(), this should
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help performance on machines with lots of tunnels.
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o Dispatching for de-capsulating packets is now via protosw[], making
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reception of other raw protocols more efficient
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o Neighbor capabilities are discovered via a bitmask as opposed to
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version number.
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o Multicast traceroute code improved
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o mrouted can be compiled with Routing Support for Resource Reservation
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(RSRR), required for RSVP.
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The 3.5 release fixes the following bugs:
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o The IGMPv2 query timeout field was interpreted as being in units of
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200ms as opposed to 100ms, thus the maximum timeout was set to twice
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the expected value. This is not fatal, as mrouted always queries
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twice in the expectation that a packet could get loss, but it does
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make it less robust in the face of packet loss.
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o IGMP could report membership in local-only groups (i.e. 224.0.0.X)
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o IGMP could get confused by hearing its own new membership reports, thus
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a router would never perform fast leave.
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o IGMP could reset timers for the wrong interface.
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o mrouted put a bogus value in the maximum timeout field of IGMPv2 query
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packets.
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o Non-querier mrouters would respond to IGMP leave messages
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o mrouted was not performing fast leave properly
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o If the last member goes away on a transit network, the upstream router
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would stop forwarding even if there are downstream members.
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o Kernel hash function improved
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o Eliminated possibility of panic(): timeout in cache maintenance
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o Reordered resource allocation when sending upcall to handle failure properly
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o some endian-ness bugs squashed in mrouted, probably more to go.
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o Multicast traceroute could send a reply on a disabled interface.
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This release consists of the following files:
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README-3.8.mrouted - this file
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mrouted/* - version 3.8 of mrouted,
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mrinfo, map-mbone and
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mtrace.
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ifconfig/* - Changes to ifconfig to
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show multicast interfaces
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netstat/* - Diffs to netstat
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ping/* - sources for ping
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which support
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multicasting
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mtest/* - utility for testing
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multicast group
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membership
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MROUTED 3.8
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Mrouted 3.8 has two optional features: SNMP and RSRR. RSRR support
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is required for running RSVP; the SNMP code, with the help of the
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ISODE snmpd, implements both the Multicast MIB and the DVMRP MIB.
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RSRR
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----
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Routing Support for Resource Reservations (RSRR) was contributed by
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Daniel Zappala <daniel@isi.edu>.
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To enable RSRR support, uncomment the three lines starting with
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RSRR near the top of the Makefile and "make clean; make". Or use
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the prebuilt binary, mrouted.rsrr .
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RSRR allows RSVP to query mrouted for its routing entry for a particular
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source-group pair. Using the routing entry and the IP_MULTICAST_VIF
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socket call, RSVP can forward distinct control messages out each
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outgoing interface. This version of mrouted supports RSRR messages
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using a Unix datagram socket.
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RSRR currently includes two pairs of query-reply messages. RSVP sends
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an Initial Query when it starts. Mrouted responds with an Initial Reply
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that includes the set of vifs it is using, flagging those that are
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administratively disabled. When RSVP needs the routing entry for a
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source-group pair, it sends a Route Query. Mrouted responds with a
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Route Reply that includes the incoming vif and outgoing vifs for the
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source-group pair.
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RSVP may request route change notification by setting the notification
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bit in the Route Query. If mrouted can provide route change
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notification for the source-group pair, it sets the notification bit in
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its Route Reply. When the routing entry for the source-group pair
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changes, mrouted sends an unsolicited Route Reply containing the new
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routing information. The initial release of mrouted 3.5 did not support
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route change notification and always returned a Route Reply with the
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notification bit cleared. This release of mrouted provides route change
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notification when possible.
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SNMP
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----
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SNMP support was contributed by David Thaler <thalerd@eecs.umich.edu>.
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To enable SNMP support, uncomment the six lines near the top of
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the Makefile below the description of SNMP support, or use the
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prebuilt binary, mrouted.snmp or mrouted.rsrr.snmp .
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To link the SNMP-capable mrouted, you need the CMU libraries.
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See http://nic.merit.edu/~mbone/ for a full mrouted-snmp distribution.
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Make sure to add the "sysName", "sysContact", "sysVersion" and
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"sysLocation" variables to your /etc/mrouted.conf if you want them
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to provide anything other than default values.
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Example:
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sysName "tibia"
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sysContact "Bill Fenner <fenner@parc.xerox.com> +1 415 812-4816"
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sysVersion "SunOS 4.1.3 and mrouted 3.8"
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sysLocation "MAXC room, PARC building 35"
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The SNMP version of mrouted has an additional command line flag:
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-P snmp_port
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Specifies a port for SNMP communication (default 161). This option
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should be used when another SNMP daemon already exists. The
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preferred alternate port in this case is port 9161.
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The mstat(8) program allows querying of statistics using SNMP.
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