vfs.fs.size returns ZBX_NOTSUPPORTED on large file systems. This is a big problem in our environment as we have many large file systems that we need to monitor.

output from df -h:
store01/backup/depot 23T 241G 19T 2% /store01/backup/depot
store01/backup/prod 23T 3.7T 19T 17% /store01/backup/prod
store01/backup/uunas01 1.0T 77G 947G 8% /store01/backup/uunas01
store01/dws/dws_admin 75G 3.3G 71G 5% /store01/dws/dws_admin
store01/logs/syslogs 2.0T 1.5T 553G 73% /store01/logs/syslogs

[root@mon02 ~]# zabbix_get -s store01.prod.sea2.cmates.com -k vfs.fs.size[/store01/backup/depot,pfree]
ZBX_NOTSUPPORTED
[root@mon02 ~]# zabbix_get -s store01.prod.sea2.cmates.com -k vfs.fs.size[/store01/backup/prod,pfree]
ZBX_NOTSUPPORTED
[root@mon02 ~]# zabbix_get -s store01.prod.sea2.cmates.com -k vfs.fs.size[/store01/backup/uunas01,pfree]
92.433821
[root@mon02 ~]# zabbix_get -s store01.prod.sea2.cmates.com -k vfs.fs.size[/store01/dws/dws_admin,pfree]
95.622716
[root@mon02 ~]# zabbix_get -s store01.prod.sea2.cmates.com -k vfs.fs.size[/store01/dws/dws_admin,free]
74927331
[root@mon02 ~]# zabbix_get -s store01.prod.sea2.cmates.com -k vfs.fs.size[/store01/backup/depot,free]
ZBX_NOTSUPPORTED
[root@mon02 ~]# zabbix_get -s store01.prod.sea2.cmates.com -k vfs.fs.size[/store01/logs/syslogs,free]
ZBX_NOTSUPPORTED
[root@mon02 ~]# zabbix_get -s store01.prod.sea2.cmates.com -k vfs.fs.size[/store01/logs/syslogs,pfree]
ZBX_NOTSUPPORTED