When I moved from Slackware 14 (on a HDD) to Slackware 14.2 (on a SSD) most of the time I was not online after the system had started. Restarting rc.inet1 one or two times got me eventually online, but felt not as a real solution. Changing the timeout from 10 to 25 in the following line in /etc/rc.d/rc.inet1 did fix it.
/sbin/dhcpcd -t ${DHCP_TIMEOUT[$i]:-25} ${DHCP_OPTIONS} ${1}
