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Annotation of embedaddon/pimd/FAQ.md, revision 1.1.1.1

1.1       misho       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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