wifi connection lost upon restart

I have a mac mini late 2012 running Mavericks server. it has both ethernet and wireless capabilities and i am using both. wireless seems to work well, except when i reboot. when I reboot the mini, I get the exclamation point saying there is no internet access. turning off wireless and turning it on again solves the problem. does anyone else have this problem? seems very annoying to have to reset it every time i do a reboot.