Maybe to assist is could you respond with:
1. What version of Junos are you using?
2. What is the exact log message you [were] seeing?
3. Where is the DHCP Server located ? Is there just one (maybe redundant)? What IP address and is it in a different VLAN to your VLANs on the EX2300?
4. What does interface ge-0//0/17 actually connect to? Device and its config?
This might be a start, . . .