Infrastructure Software

Hi everybody

Pls solve my problem

I get the following message when trying to tar up cold backup of server

tar: Error exit delayed from previous errors

i cant understand what the error means ,i just want to know about ,is my backup is right or wrong,
this error comes at the /dir3 directory.

the tar command that i using
tar -cvf /dev/st0 /dir1 /dir2 /dir3

pls Help me

Thanks