You know that the 5005 error is really generic. Could you check the server_log following the attempt and see if there are any error messages that might clue you in as to what the issue is? Perhaps you could also check the sys_log in /nas/log as well.

looking deeper I see the following...

"Incorrect Reference on volume 5998" in the Celerra Manager GUI...


[nasadmin@ns01cs0 ~]$ nas_volume -info d774
id = 5998
name = d774
acl = 0
in_use = True
pool = clar_r5_performance_2
type = disk
disk_name = d774
disks = d774
clnt_slices = s2592,s2720,s2915,s2724,s2745

[nasadmin@ns01cs0 ~]$ nas_fs -i msfs05_data |more <-- File system ckpts fail on
id = 12996
name = msfs05_data
[...]
disk=d774 stor_dev=APM00071601447-00FA addr=c48t1l6 server=server_2
disk=d774 stor_dev=APM00071601447-00FA addr=c96t1l6 server=server_2
disk=d774 stor_dev=APM00071601447-00FA addr=c32t1l6 server=server_2
disk=d774 stor_dev=APM00071601447-00FA addr=c64t1l6 server=server_2

Hi. I'd recommend you open a case with EMC support for this issue. They should be able to help to figure out what is going on with your file system.
Cheers.
-Dan