1udhcp server (udhcpd) 2-------------------- 3 4The only command line argument to udhcpd is an optional specifed 5config file. If no config file is specified, udhcpd uses the default 6config file, /etc/udhcpd.conf. Ex: 7 8udhcpd /etc/udhcpd.eth1.conf 9 10The udhcp server employs a number of simple config files: 11 12udhcpd.leases 13------------ 14 15The udhcpd.leases behavior is designed for an embedded system. The 16file is written either every auto_time seconds, or when a SIGUSR1 17is received (the auto_time timer restarts if a SIGUSR1 is received). 18If you send a SIGTERM to udhcpd directly after a SIGUSR1, udhcpd will 19finish writing the leases file and wait for the aftermentioned script 20to be executed and finish before quiting, so you do not need to sleep 21between sending signals. When the file is written, a script can be 22optionally called to commit the file to flash. Lease times are stored 23in the file by time remaining in lease (for systems without clock 24that works when there is no power), or by the absolute time that it 25expires in seconds from epoch. In the remaining format, expired leases 26are stored as zero. The file is of the format: 27 2816 byte MAC 294 byte ip address 30u32 expire time 3116 byte MAC 324 byte ip address 33u32 expire time 34. 35etc. 36 37example: hexdump udhcpd.leases 38 390000000 1000 c95a 27d9 0000 0000 0000 0000 0000 400000010 a8c0 150a 0d00 2d29 5000 23fc 8566 0000 410000020 0000 0000 0000 0000 a8c0 140a 0d00 4e29 420000030 43 44 45udhcpd.conf 46---------- 47 48The format is fairly simple, there is a sample file with all the 49available options and comments describing them in samples/udhcpd.conf 50 51compile time options 52------------------- 53 54dhcpd.h contains the other two compile time options: 55 56 LEASE_TIME: The default lease time if not specified in the config 57 file. 58 59 DHCPD_CONFIG_FILE: The defualt config file to use. 60