question about recovery primary gpt table

[Jimmy Fan]

Hi all
I have got couple of error notice during boot process. 

Trying to mount root from ufs:/dev/ad4s1a
GEOM: ad6: the primary GPT table is corrupt or invalid.
GEOM: ad6: using the secondary instead -- recovery strongly advised.
GEOM: ad8: the primary GPT table is corrupt or invalid.
GEOM: ad8: using the secondary instead -- recovery strongly advised.
GEOM: ad10: the primary GPT table is corrupt or invalid.
GEOM: ad10: using the secondary instead -- recovery strongly advised.
nfe0: link state changed to UP

regarding google result. I can fix it by using gpt recover method.
no luck, im using 8.0 there is no such program in the system. could
anybody tell me how I can fix it. it is really annoy me.

Jimmy Fan

-- 
I will save your computer!