{ "content": [ { "type": "text", "text": "# ndisc6 (man)\n\n## NAME\n\nndisc6 - ICMPv6 Neighbor Discovery tool\n\n## SYNOPSIS\n\nndisc6 [-1mnqv] [-r attempts] [-s sourceip] [-w waitms] \n\n## Sections\n\n- **NAME**\n- **SYNOPSIS**\n- **DESCRIPTON**\n- **OPTIONS** (10 subsections)\n- **DIAGNOSTICS**\n- **SECURITY**\n- **SEE ALSO**\n- **AUTHOR**\n\nUse structuredContent.sections for detailed options, examples, and full documentation.\n" } ], "structuredContent": { "command": "ndisc6", "section": "", "mode": "man", "summary": "ndisc6 - ICMPv6 Neighbor Discovery tool", "synopsis": "ndisc6 [-1mnqv] [-r attempts] [-s sourceip] [-w waitms] ", "tldr_summary": null, "tldr_examples": [], "tldr_source": null, "flags": [ { "flag": "-1", "long": "--single", "arg": null, "description": "Exit as soon as the first advertisement is received (default)." }, { "flag": "-h", "long": "--help", "arg": null, "description": "Display some help and exit." }, { "flag": "-m", "long": "--multiple", "arg": null, "description": "Wait for possible duplicate advertisements and print all of them." }, { "flag": "-n", "long": "--numeric", "arg": null, "description": "If the first parameter is not a valid IPv6 address, do not try to resolve it as a DNS hostname." }, { "flag": "-q", "long": "--quiet", "arg": null, "description": "Only display link-layer address. Display nothing in case of failure. That is mostly useful when calling the program from a shell script." }, { "flag": "-r", "long": "--retry", "arg": null, "description": "Send ICMPv6 Neighbor Discovery that many times until a reply is received, or abort. By default, ndisc6 will try 3 times before aborting (MAXMULTICASTSOLICIT and MAXUNI‐ CASTSOLICIT from RFC2461)." }, { "flag": "-s", "long": "--source", "arg": null, "description": "Specify the IPv6 address to be used as the source for the neighbor solicitation pack‐ ets." }, { "flag": "-V", "long": "--version", "arg": null, "description": "Display program version and license and exit." }, { "flag": "-v", "long": "--verbose", "arg": null, "description": "Display verbose information. That is the default." }, { "flag": "-w", "long": "--wait", "arg": null, "description": "Wait waitms milliseconds for a response before retrying. By default, ndisc6 waits 1 second between each attempts (RETRANSTIMER from RFC2461). If ndisc6 does not receive any response after the specified number of attempts waiting for waitms milliseconds each time, it will exit with code 2. On error, it exits with code 1. Otherwise it exits with code 0. This makes it possible to use the exit code to see if a host is on-link or not." } ], "examples": [], "see_also": [ { "name": "ping6", "section": "8", "url": "https://www.chedong.com/phpMan.php/man/ping6/8/json" }, { "name": "rdisc6", "section": "8", "url": "https://www.chedong.com/phpMan.php/man/rdisc6/8/json" }, { "name": "ipv6", "section": "7", "url": "https://www.chedong.com/phpMan.php/man/ipv6/7/json" } ], "section_outline": [ { "name": "NAME", "lines": 2, "subsections": [] }, { "name": "SYNOPSIS", "lines": 3, "subsections": [] }, { "name": "DESCRIPTON", "lines": 8, "subsections": [] }, { "name": "OPTIONS", "lines": 1, "subsections": [ { "name": "-1 --single", "lines": 3, "flag": "-1", "long": "--single" }, { "name": "-h --help", "lines": 3, "flag": "-h", "long": "--help" }, { "name": "-m --multiple", "lines": 3, "flag": "-m", "long": "--multiple" }, { "name": "-n --numeric", "lines": 4, "flag": "-n", "long": "--numeric" }, { "name": "-q --quiet", "lines": 4, "flag": "-q", "long": "--quiet" }, { "name": "-r attempts --retry attempts", "lines": 5, "flag": "-r", "long": "--retry" }, { "name": "-s source_ip --source source_ip", "lines": 4, "flag": "-s", "long": "--source" }, { "name": "-V --version", "lines": 3, "flag": "-V", "long": "--version" }, { "name": "-v --verbose", "lines": 3, "flag": "-v", "long": "--verbose" }, { "name": "-w wait_ms --wait wait_ms", "lines": 10, "flag": "-w", "long": "--wait" } ] }, { "name": "DIAGNOSTICS", "lines": 9, "subsections": [] }, { "name": "SECURITY", "lines": 5, "subsections": [] }, { "name": "SEE ALSO", "lines": 3, "subsections": [] }, { "name": "AUTHOR", "lines": 5, "subsections": [] } ], "sections": { "NAME": { "content": "ndisc6 - ICMPv6 Neighbor Discovery tool\n", "subsections": [] }, "SYNOPSIS": { "content": "ndisc6 [-1mnqv] [-r attempts] [-s sourceip] [-w waitms] \n\n", "subsections": [] }, "DESCRIPTON": { "content": "NDisc6 is an Unix program which implements the ICMPv6 Neighbor Discovery in userland (it is\nnormally done by the kernel). It is used to lookup the link-layer address (layer 2 address,\nMAC in the case of Ethernet) of any on-link IPv6 node.\n\nThe IPv6 address of the node must be specified, as well as the networking interface on which\nto perform the lookup.\n\n", "subsections": [] }, "OPTIONS": { "content": "", "subsections": [ { "name": "-1 --single", "content": "Exit as soon as the first advertisement is received (default).\n\n", "flag": "-1", "long": "--single" }, { "name": "-h --help", "content": "Display some help and exit.\n\n", "flag": "-h", "long": "--help" }, { "name": "-m --multiple", "content": "Wait for possible duplicate advertisements and print all of them.\n\n", "flag": "-m", "long": "--multiple" }, { "name": "-n --numeric", "content": "If the first parameter is not a valid IPv6 address, do not try to resolve it as a DNS\nhostname.\n\n", "flag": "-n", "long": "--numeric" }, { "name": "-q --quiet", "content": "Only display link-layer address. Display nothing in case of failure. That is mostly\nuseful when calling the program from a shell script.\n\n", "flag": "-q", "long": "--quiet" }, { "name": "-r attempts --retry attempts", "content": "Send ICMPv6 Neighbor Discovery that many times until a reply is received, or abort. By\ndefault, ndisc6 will try 3 times before aborting (MAXMULTICASTSOLICIT and MAXUNI‐\nCASTSOLICIT from RFC2461).\n\n", "flag": "-r", "long": "--retry" }, { "name": "-s source_ip --source source_ip", "content": "Specify the IPv6 address to be used as the source for the neighbor solicitation pack‐\nets.\n\n", "flag": "-s", "long": "--source" }, { "name": "-V --version", "content": "Display program version and license and exit.\n\n", "flag": "-V", "long": "--version" }, { "name": "-v --verbose", "content": "Display verbose information. That is the default.\n\n", "flag": "-v", "long": "--verbose" }, { "name": "-w wait_ms --wait wait_ms", "content": "Wait waitms milliseconds for a response before retrying. By default, ndisc6 waits 1\nsecond between each attempts (RETRANSTIMER from RFC2461).\n\n\nIf ndisc6 does not receive any response after the specified number of attempts waiting for\nwaitms milliseconds each time, it will exit with code 2. On error, it exits with code 1.\nOtherwise it exits with code 0. This makes it possible to use the exit code to see if a host\nis on-link or not.\n\n", "flag": "-w", "long": "--wait" } ] }, "DIAGNOSTICS": { "content": "If you get no response while you know the remote host is up, it is most likely that it is not\non-link, that is to say, you must cross one or more routers to reach it. By design, IPv6\nnodes ignore ICMPv6 Neighbor Discovery packets received from nodes not on the same link (i.e.\nEthernet segment), for the sake of security. Technically, that is done by ensuring that the\nHop limit (TTL) is 255.\n\nNote that you cannot use ndisc6 to lookup the local host's link-layer address.\n\n", "subsections": [] }, "SECURITY": { "content": "ndisc6 should be setuid root to allow use by non-privileged users. It will drop its root\nprivileges before any attempt is made to send or receive data from the network to reduce the\npossible impact of a security vulnerability.\n\n", "subsections": [] }, "SEE ALSO": { "content": "ping6(8), rdisc6(8), ipv6(7)\n\n", "subsections": [] }, "AUTHOR": { "content": "Rémi Denis-Courmont \n\nhttp://www.remlab.net/ndisc6/\n\nndisc6 $Date$ NDISC6(8)", "subsections": [] } } } }