There is a command in NNMi to delete a seed... i.e single seed using nnmseeddelete.ovpl
nnmseeddelete.ovpl — Remove seed from the NNM topology database
Unfortunately this command does not have option to specify for all seeds. Probably you might need to do what I did to delete some 300+ seeds ( we dont use auto discovery ) from our NNMi production server...
From NNMi shell, execute :
for node in `cat /tmp/seeds.txt`; do /opt/OV/bin/nnmseeddelete.ovpl -seed $node -u NNMiadminUserName -p NNMiadminPassword; done
/tmp/seeds.txt - list of seeds ( one seed per line ) to be deleted.