GDPD

Section: Maintenance Commands (8)
Updated: 20 September 1989
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NAME

gdpd - Gateway Discover Protocol Daemon

SYNOPSIS

gdpd [ -d ] [ -f ] [ -h hold-time ] [ -l ] [ -m metric ] [ -p priority ] [ -q query-time ] [ -r report-time ] [ -t cycle-time ] [ IP-address ... ]

DESCRIPTION

The gdpd implements the cisco Gateway Discovery Protocol. This protocol permits hosts to discover routers on a connected network. Multiple routers can be running the GDP and hosts can choose to use one or more of them to forward traffic. Hosts listening for GDP messages can learn when a router goes down or when a new router comes up. The GDP is implemented above the UDP and listens on port number 1997 decimal.

This implementation will act as both GDP server and client. That is, it can perform both router and host functions but not simultaneously. The switches described below will determine whether the daemon is acting as a listener or server.

When acting as a server, GDP REPORT messages are sent at regular intervals and QUERY messages are answered. All network interfaces that are up and running and are assigned an IP address will participate in the protocol. When acting as a client, all network interfaces that are up and running and are assigned IP addresses will receive GDP messages. A GDP QUERY message is sent to each interface's broadcast address when the daemon first starts up. GDP REPORT messages are processed but QUERY messages are ignored. IP addresses can be specified and GDP QUERY messages will be sent directly to that address at periodic intervals. The best router or collection of routers will be used as the default route.

OPTIONS

-d: Enable debugging information via syslog(8) messages.
-f: Will flush all routes via router that times out or stops sending reports. This makes sure redirects are removed from the routing table so new routes can be learned.
-h hold-time: Sets the holding time value in the GDP REPORT messages when -r is used. The default value is 15 seconds.
-l: Enable logging of interesting events via syslog(8). Interesting events are changing routes, flushing the ARP cache, etc. Normally gdpd runs silently.
-m metric: When setting the default route, use this value as the metric. If zero is specified, proxy ARP is presumed to be in use and the ARP cache will be cleared when the default route changes. The default metric is 1.
-p priority: Specifies the priority value in the GDP REPORT messages when -r is used. The default value is 100.
-q query-time: When running over interfaces which do not support broadcast or multicast, a query interval can be specified so QUERY messages can be sent directly to specified IP peers. By default, this value is not set.
-r report-time: Force the daemon to send REPORT messages at the specified interval in seconds. This flag should be used when the host is acting as a router. By default, this value is not set.
-t cycle-time: When multiple routers are using the same priority value, normally the first router learned will be used as default. If this flag is used, each router at the highest priority will be used in a round-robin fashion for cycle-time minutes.

BUGS

The -r option for sending REPORT messages isn't finished.

This document was created by man2html, using the manual pages.
Time: 13:12:39 GMT, November 04, 2024