Return to README-debug.md CVS log

Up to [ELWIX - Embedded LightWeight unIX -] / embedaddon / pimd

Annotation of embedaddon/pimd/README-debug.md, revision 1.1

1.1     ! misho       1: > $Id: README.debug,v 1.4 2002/11/17 20:01:31 pavlin Exp $
        !             2: 
        !             3: This file contains some hints how to debug your multicast routing.
        !             4: 
        !             5: **NOTE:** currently, it is very incomplete.  If something is missing
        !             6:              and/or unclear, email to the current maintainer of pimd or
        !             7:              file an issue in the GitHub issue tracker.
        !             8: 
        !             9: 1. Make sure that the TTL of the sender is large enough to reach the
        !            10:    receiver. E.g., if the sender and the receiver are separated by a
        !            11:    two routers in the middle, the TTL of the data packets transmitted
        !            12:    by the sender must be at least 3.
        !            13: 
        !            14: 2. Make sure the receiver sends IGMP join (membership report) for the
        !            15:    group(s) it wants to receive.  Use tcpdump on the router closest to
        !            16:    the receiver to make sure.  Sometimes buggy IGMP snooping switches,
        !            17:    or cloud provider networks, filter out multicast in general, or all
        !            18:    control traffic (IGMP/PIM) in particular.
        !            19: 
        !            20: 3. Before you start the multicast routing daemon, verify the kernel
        !            21:    config, the following settings should be activated:
        !            22: 
        !            23:    - On Linux:
        !            24: 
        !            25:                 CONFIG_IP_MROUTE=y
        !            26:                 CONFIG_IP_PIMSM_V1=y
        !            27:                 CONFIG_IP_PIMSM_V2=y
        !            28:                 CONFIG_IP_MROUTE_MULTIPLE_TABLES=y    # Optional
        !            29: 
        !            30:      Check the list of multicast capable interfaces:
        !            31: 
        !            32:                 cat /proc/net/dev_mcast
        !            33: 
        !            34:    - On *BSD:
        !            35: 
        !            36:                 options    MROUTING         # Multicast routing
        !            37:                 options    PIM              # Enable for pimd
        !            38: 
        !            39:    - Start the multicast routing daemon in debug mode.  E.g., `pimd -dall`
        !            40:         or if you just want to see some subystems: `pimd -drpf,mrt -s7`
        !            41: 
        !            42: 4. After you start the multicast routing daemon
        !            43: 
        !            44:    - Are the multicast vifs correctly installed in the kernel:
        !            45: 
        !            46:         - On Linux:
        !            47: 
        !            48:                 cat /proc/net/ip_mr_vif
        !            49: 
        !            50:         - On *BSD:
        !            51: 
        !            52:                 netstat -gn
        !            53: 
        !            54:  - Is multicast forwarding enabled on those vifs:
        !            55: 
        !            56:         - On Linux:
        !            57: 
        !            58:                 sysctl net.ipv4.conf.eth0.mc_forwarding
        !            59: 
        !            60:           For each of the enabled interfaces.  If it returns zero, the
        !            61:           multicast forwarding on that interface is not working.
        !            62: 
        !            63:         - On *BSD:
        !            64: 
        !            65:                 sysctl net.inet.ip.forwarding
        !            66:                 sysctl net.inet.ip.mforwarding      # Only OpenBSD
        !            67: 
        !            68:  - Is the PIM multicast routing daemon exchanging `PIM_HELLO` messages
        !            69:    with its neighbors?  Look into the debug messages output; if
        !            70:    necessary, use `tcpdump` as well.
        !            71: 
        !            72:  - Are the Bootpstrap messages received by all PIM-SM daemons?
        !            73: 
        !            74:  - If a Bootstrap message is received, is it accepted, or is it
        !            75:    rejected because of a wrong iif?
        !            76: 
        !            77:  - After a while, does the Cand-RP set contain the set of RPs?
        !            78: 
        !            79:  - After the first multicast packets are received, is there `CACHE_MISS`
        !            80:    signal from the kernel to the user-level daemon?
        !            81: 
        !            82:  - After the `CACHE_MISS` signal, are the MFC (Multicast Forwarding Cache)
        !            83:    entries installed in the kernel?
        !            84:  
        !            85:         - On Linux:
        !            86: 
        !            87:                 cat /proc/net/ip_mr_cache
        !            88: 
        !            89:         - On *BSD:
        !            90: 
        !            91:                 netstat -gn
        !            92: 
        !            93: <!--
        !            94:   -- Local Variables:
        !            95:   -- mode: markdown
        !            96:   -- End:
        !            97:   -->