When executing an invalid command such as:

/usr/sbin/vdlimit --xid 300 --set space_total=2000000 --set space_used=3020400 --set inodes_total=2000000 --set inodes_used=3 --set reserved=5 /vservers/test/

vdlimit reports the following error:

vdlimit: vc_set_dlimit(): Invalid argument

But vdlimit has already performed vc_add_limit() and sets the values at 0, causing disk space problems on the vserver.

The validation of the values needs to be performed before executing vc_add_limit(), so that invalid results can not be set.

Also, more detailed error messages may also help.  In this example, the error might include the information that space_used can not be larger then the space_total.

(Note: The invalid results were obtained by dynamically assigning the space_used based off of current usages.)