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pimd 2.3.2

    1: Mini FAQ
    2: ========
    3: 
    4: * Q: My RP is a Cisco router, but it doesn't work with pimd?
    5: 
    6:   If your Cisco is running PIM-SMv1, it won't work with pimd which
    7:   implements only PIM-SMv2.  You need to upgrade/configure your Cisco to
    8:   run PIM-SMv2.
    9: 	
   10:   If your Cisco is indeed running PIM-SMv2, and it is the RP, you need
   11:   to run the pimd `configure` script with `--enable-broken-crc` defined.
   12:   See the beginning of the configure script, or the output from the
   13:   command `configure --help`.  Note that this will then likely cause the
   14:   PIM Register messages to *not* be accepted by some other vendors, but
   15:   pimd-to-pimd should still be OK.
   16: 
   17:   **Note:** This is a *very* old FAQ and this issue is exteremly likely
   18:   to be rather reversed in 2015 ...
   19: 
   20: * Q: Do I need to re-configure my Linux kernel to run pimd?
   21: 
   22:   Maybe, most major GNU/Linux distributions today ship with multicast
   23:   capable Linux kernels.  However, do make a habit of verifying that
   24:   you have at least the following:
   25: 
   26: 	    CONFIG_IP_MULTICAST
   27: 		CONFIG_IP_PIMSM_V2
   28: 		CONFIG_IP_MROUTE
   29: 
   30:   You *may* enable `CONFIG_IP_PIMSM_V1` as well, but it is likely not
   31:   required to interop with any active equipment anymore.  What may cause
   32:   you to have to recompile Linux in 2015 is the lack of multiple
   33:   multicast routing tables.  My Ubuntu 15.04 lists the following in its
   34:   `/boot/config-3.19.0-23-generic`:
   35: 
   36: 		# CONFIG_IP_MROUTE_MULTIPLE_TABLES is not set
   37: 
   38:   Also, make sure to check that NETLINK related settings are enabled,
   39:   because that is the interface pimd uses on Linux, not routing sockets
   40:   anymore.  Again, very likely to be default in 2015.
   41: 
   42:   Make sure that those options are set to "y" to include the relevant
   43:   code in the kernel; if you enable them as modules, then you may have
   44:   to load that module after you boot with the new kernel.  One way to
   45:   find-out if multicast routing is not working, is to use command `cat
   46:   /proc/sys/net/ipv4/conf/eth0/mc_forwarding` after you have started
   47:   pimd (you may use other interface name instead of `eth0`).  If it
   48:   returns zero, multicast forwarding on that interface is not working.
   49: 
   50: * Q: I tried pimd on Linux, but I get the following error message:
   51: 
   52: 		netlink socket: Address family not supported by protocol
   53: 
   54:   You need to enable the NETLINK related stuff in the kernel and
   55:   recompile it.
   56: 
   57: * Q: pimd compiled and is running on a single machines, but when I run
   58:   it on 2+ machines, the multicast packets do not reach the receivers.
   59: 
   60:   Without detailed debug information I cannot answer this question.
   61:   Please send to the pimd maintainer a scheme (topology map) of your
   62:   network, and the debug output from each router (`pimd -dall`), that
   63:   may help.
   64: 
   65: * Q: How do I debug my multicast routing?
   66: 
   67:   Check [README-debug.md][debug] for some hints.
   68: 
   69: * Q: How do I use pimd with GRE tunnels?
   70: 
   71:   See the file [README-config.md][config] for examples.
   72: 
   73: * Q: How do I run pimd but without configuring it as a Cand-RP and/or a
   74:   Cand-BSR?
   75: 
   76:   See the file [README-config.md][config] for details.
   77: 
   78: * Q: I have set the `phyint dr-priority` to 10, but another router is
   79:   still elected as DR, why?
   80: 
   81:   This happens when not all routers on a LAN advertise the *DR Priority*
   82:   option in PIM Hello messages.  Check with tcpdump or wireshark to find
   83:   the culprit.  Versions of pimd older than v2.3.0 did not support the
   84:   *DR Priority* option.
   85: 
   86: * Q: How do I configure pimd to do FOO?
   87: 
   88:   See file [README-config.md][config].  If the answer is not there, send
   89:   an email to the current pimd maintainer, or file a bug report at the
   90:   [GitHub issue tracker][tracker].
   91: 
   92: 
   93: [debug]:   https://github.com/troglobit/pimd/blob/dev/README-debug.md
   94: [config]:  https://github.com/troglobit/pimd/blob/dev/README-config.md
   95: [tracker]: https://github.com/troglobit/pimd/issues 
   96: 
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