After upgrading the EX4550 device to 15.1 DHCP is not working for the Default vlan
Upgraded 2 X EX4550 VC from Junos 12.3R12-S20 to 15.1R7-S11.1 version.
Post upgrade, DHCP is not working for default vlan
core mgd[39892]: UI_CMDLINE_READ_LINE: User 'root', command 'request system software add /var/tmp/jinstall-ex-4500-15.1R7-S11.1-domestic-signed.tgz no-validate '
core mgd[40911]: UI_CMDLINE_READ_LINE: User 'root', command 'request system reboot'
Noticed the default DHCP configuration was enabled for default vlan and vme interface
delete interfaces vlan unit 0 family inet dhcp vendor-id Juniper-ex4550-32f
delete interfaces vme unit 0 family inet dhcp vendor-id Juniper-ex4550-32f
After removing the default configuration for default vlan and vme interface, DHCP services started to work as expected.