2002-11-01 00:51:27 +05:30
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udhcp server (udhcpd)
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The only command line argument to udhcpd is an optional specifed
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config file. If no config file is specified, udhcpd uses the default
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config file, /etc/udhcpd.conf. Ex:
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udhcpd /etc/udhcpd.eth1.conf
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The udhcp server employs a number of simple config files:
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udhcpd.leases
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------------
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The udhcpd.leases behavior is designed for an embedded system. The
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file is written either every auto_time seconds, or when a SIGUSR1
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2004-03-15 13:59:22 +05:30
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is received (the auto_time timer restarts if a SIGUSR1 is received).
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2002-11-01 00:51:27 +05:30
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If you send a SIGTERM to udhcpd directly after a SIGUSR1, udhcpd will
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finish writing the leases file and wait for the aftermentioned script
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to be executed and finish before quiting, so you do not need to sleep
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between sending signals. When the file is written, a script can be
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optionally called to commit the file to flash. Lease times are stored
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in the file by time remaining in lease (for systems without clock
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that works when there is no power), or by the absolute time that it
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expires in seconds from epoch. In the remaining format, expired leases
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are stored as zero. The file is of the format:
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16 byte MAC
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4 byte ip address
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u32 expire time
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16 byte MAC
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4 byte ip address
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u32 expire time
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.
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etc.
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example: hexdump udhcpd.leases
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0000000 1000 c95a 27d9 0000 0000 0000 0000 0000
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0000010 a8c0 150a 0d00 2d29 5000 23fc 8566 0000
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0000020 0000 0000 0000 0000 a8c0 140a 0d00 4e29
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0000030
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udhcpd.conf
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----------
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The format is fairly simple, there is a sample file with all the
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available options and comments describing them in samples/udhcpd.conf
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compile time options
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-------------------
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2004-03-15 13:59:22 +05:30
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2002-11-01 00:51:27 +05:30
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dhcpd.h contains the other two compile time options:
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2004-03-15 13:59:22 +05:30
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2002-11-01 00:51:27 +05:30
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LEASE_TIME: The default lease time if not specified in the config
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file.
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2004-03-15 13:59:22 +05:30
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2002-11-01 00:51:27 +05:30
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DHCPD_CONFIG_FILE: The defualt config file to use.
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