I have been asked by a user why the PRTG snmp disk sensors dont match the linux df command, I have done an snmpwalk and checked the figures of both snmp and df adn the are identical.
But the figure in PRTG is off by a big margin, could you explain this?
DF - h = 25Gb PRTG = 63,254 MByte
Article Comments
Hi Greg,
see below for df -h, snmpwalk and snmp tester.
[sciteqmh@iaptusvnode1 ~]$ df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg_maydenasvnode1-lv_root
77G 21G 52G 29% /
tmpfs 3.9G 0 3.9G 0% /dev/shm
/dev/sda1 485M 63M 397M 14% /boot
/dev/sdb1 739G 678G 24G 97% /mnt/iaptus_docs
/dev/sdc1 148G 125G 16G 89% /mnt/iaptus_docs1
[sciteqmh@iaptusvnode1 ~]$ snmpwalk -v 2c -c ???????? 127.0.0.1 HOST-RESOURCES-MIB::hrStorage HOST-RESOURCES-MIB::hrMemorySize.0 = INTEGER: 8194320 KBytes HOST-RESOURCES-MIB::hrStorageIndex.1 = INTEGER: 1 HOST-RESOURCES-MIB::hrStorageIndex.3 = INTEGER: 3 HOST-RESOURCES-MIB::hrStorageIndex.6 = INTEGER: 6 HOST-RESOURCES-MIB::hrStorageIndex.7 = INTEGER: 7 HOST-RESOURCES-MIB::hrStorageIndex.10 = INTEGER: 10 HOST-RESOURCES-MIB::hrStorageIndex.31 = INTEGER: 31 HOST-RESOURCES-MIB::hrStorageIndex.35 = INTEGER: 35 HOST-RESOURCES-MIB::hrStorageIndex.36 = INTEGER: 36 HOST-RESOURCES-MIB::hrStorageIndex.37 = INTEGER: 37 HOST-RESOURCES-MIB::hrStorageIndex.38 = INTEGER: 38 HOST-RESOURCES-MIB::hrStorageType.1 = OID: HOST-RESOURCES-TYPES::hrStorageRam HOST-RESOURCES-MIB::hrStorageType.3 = OID: HOST-RESOURCES-TYPES::hrStorageVirtualMemory HOST-RESOURCES-MIB::hrStorageType.6 = OID: HOST-RESOURCES-TYPES::hrStorageOther HOST-RESOURCES-MIB::hrStorageType.7 = OID: HOST-RESOURCES-TYPES::hrStorageOther HOST-RESOURCES-MIB::hrStorageType.10 = OID: HOST-RESOURCES-TYPES::hrStorageVirtualMemory HOST-RESOURCES-MIB::hrStorageType.31 = OID: HOST-RESOURCES-TYPES::hrStorageFixedDisk HOST-RESOURCES-MIB::hrStorageType.35 = OID: HOST-RESOURCES-TYPES::hrStorageFixedDisk HOST-RESOURCES-MIB::hrStorageType.36 = OID: HOST-RESOURCES-TYPES::hrStorageFixedDisk HOST-RESOURCES-MIB::hrStorageType.37 = OID: HOST-RESOURCES-TYPES::hrStorageFixedDisk HOST-RESOURCES-MIB::hrStorageType.38 = OID: HOST-RESOURCES-TYPES::hrStorageFixedDisk HOST-RESOURCES-MIB::hrStorageDescr.1 = STRING: Physical memory HOST-RESOURCES-MIB::hrStorageDescr.3 = STRING: Virtual memory HOST-RESOURCES-MIB::hrStorageDescr.6 = STRING: Memory buffers HOST-RESOURCES-MIB::hrStorageDescr.7 = STRING: Cached memory HOST-RESOURCES-MIB::hrStorageDescr.10 = STRING: Swap space HOST-RESOURCES-MIB::hrStorageDescr.31 = STRING: / HOST-RESOURCES-MIB::hrStorageDescr.35 = STRING: /dev/shm HOST-RESOURCES-MIB::hrStorageDescr.36 = STRING: /boot HOST-RESOURCES-MIB::hrStorageDescr.37 = STRING: /mnt/iaptus_docs HOST-RESOURCES-MIB::hrStorageDescr.38 = STRING: /mnt/iaptus_docs1 HOST-RESOURCES-MIB::hrStorageAllocationUnits.1 = INTEGER: 1024 Bytes HOST-RESOURCES-MIB::hrStorageAllocationUnits.3 = INTEGER: 1024 Bytes HOST-RESOURCES-MIB::hrStorageAllocationUnits.6 = INTEGER: 1024 Bytes HOST-RESOURCES-MIB::hrStorageAllocationUnits.7 = INTEGER: 1024 Bytes HOST-RESOURCES-MIB::hrStorageAllocationUnits.10 = INTEGER: 1024 Bytes HOST-RESOURCES-MIB::hrStorageAllocationUnits.31 = INTEGER: 4096 Bytes HOST-RESOURCES-MIB::hrStorageAllocationUnits.35 = INTEGER: 4096 Bytes HOST-RESOURCES-MIB::hrStorageAllocationUnits.36 = INTEGER: 1024 Bytes HOST-RESOURCES-MIB::hrStorageAllocationUnits.37 = INTEGER: 4096 Bytes HOST-RESOURCES-MIB::hrStorageAllocationUnits.38 = INTEGER: 4096 Bytes HOST-RESOURCES-MIB::hrStorageSize.1 = INTEGER: 8194320 HOST-RESOURCES-MIB::hrStorageSize.3 = INTEGER: 10258696 HOST-RESOURCES-MIB::hrStorageSize.6 = INTEGER: 8194320 HOST-RESOURCES-MIB::hrStorageSize.7 = INTEGER: 2297280 HOST-RESOURCES-MIB::hrStorageSize.10 = INTEGER: 2064376 HOST-RESOURCES-MIB::hrStorageSize.31 = INTEGER: 20007967 HOST-RESOURCES-MIB::hrStorageSize.35 = INTEGER: 1007778 HOST-RESOURCES-MIB::hrStorageSize.36 = INTEGER: 495844 HOST-RESOURCES-MIB::hrStorageSize.37 = INTEGER: 193522614 HOST-RESOURCES-MIB::hrStorageSize.38 = INTEGER: 38704122 HOST-RESOURCES-MIB::hrStorageUsed.1 = INTEGER: 6619216 HOST-RESOURCES-MIB::hrStorageUsed.3 = INTEGER: 6622424 HOST-RESOURCES-MIB::hrStorageUsed.6 = INTEGER: 321192 HOST-RESOURCES-MIB::hrStorageUsed.7 = INTEGER: 2297280 HOST-RESOURCES-MIB::hrStorageUsed.10 = INTEGER: 3208 HOST-RESOURCES-MIB::hrStorageUsed.31 = INTEGER: 5437006 HOST-RESOURCES-MIB::hrStorageUsed.35 = INTEGER: 0 HOST-RESOURCES-MIB::hrStorageUsed.36 = INTEGER: 63816 HOST-RESOURCES-MIB::hrStorageUsed.37 = INTEGER: 177590057 HOST-RESOURCES-MIB::hrStorageUsed.38 = INTEGER: 32607971
----------------------- New Test ----------------------- Paessler SNMP Tester 5.1.2 18/03/2014 12:24:33 (1 ms) : Device: 10.0.24.42 18/03/2014 12:24:33 (1 ms) : SNMP V2c 18/03/2014 12:24:33 (1 ms) : Walk 1.3.6.1.2.1.25.2 18/03/2014 12:24:33 (3 ms) : 1.3.6.1.2.1.25.2.2.0 = "8194320" 18/03/2014 12:24:33 (4 ms) : 1.3.6.1.2.1.25.2.3.1.1.1 = "1" 18/03/2014 12:24:33 (5 ms) : 1.3.6.1.2.1.25.2.3.1.1.3 = "3" 18/03/2014 12:24:33 (6 ms) : 1.3.6.1.2.1.25.2.3.1.1.6 = "6" 18/03/2014 12:24:33 (7 ms) : 1.3.6.1.2.1.25.2.3.1.1.7 = "7" 18/03/2014 12:24:33 (8 ms) : 1.3.6.1.2.1.25.2.3.1.1.10 = "10" 18/03/2014 12:24:33 (10 ms) : 1.3.6.1.2.1.25.2.3.1.1.31 = "31" 18/03/2014 12:24:33 (12 ms) : 1.3.6.1.2.1.25.2.3.1.1.35 = "35" 18/03/2014 12:24:33 (13 ms) : 1.3.6.1.2.1.25.2.3.1.1.36 = "36" 18/03/2014 12:24:33 (15 ms) : 1.3.6.1.2.1.25.2.3.1.1.37 = "37" 18/03/2014 12:24:33 (16 ms) : 1.3.6.1.2.1.25.2.3.1.1.38 = "38" 18/03/2014 12:24:33 (18 ms) : 1.3.6.1.2.1.25.2.3.1.2.1 = "1.3.6.1.2.1.25.2.1.2" 18/03/2014 12:24:33 (20 ms) : 1.3.6.1.2.1.25.2.3.1.2.3 = "1.3.6.1.2.1.25.2.1.3" 18/03/2014 12:24:33 (22 ms) : 1.3.6.1.2.1.25.2.3.1.2.6 = "1.3.6.1.2.1.25.2.1.1" 18/03/2014 12:24:33 (24 ms) : 1.3.6.1.2.1.25.2.3.1.2.7 = "1.3.6.1.2.1.25.2.1.1" 18/03/2014 12:24:33 (26 ms) : 1.3.6.1.2.1.25.2.3.1.2.10 = "1.3.6.1.2.1.25.2.1.3" 18/03/2014 12:24:33 (27 ms) : 1.3.6.1.2.1.25.2.3.1.2.31 = "1.3.6.1.2.1.25.2.1.4" 18/03/2014 12:24:33 (29 ms) : 1.3.6.1.2.1.25.2.3.1.2.35 = "1.3.6.1.2.1.25.2.1.4" 18/03/2014 12:24:33 (31 ms) : 1.3.6.1.2.1.25.2.3.1.2.36 = "1.3.6.1.2.1.25.2.1.4" 18/03/2014 12:24:33 (33 ms) : 1.3.6.1.2.1.25.2.3.1.2.37 = "1.3.6.1.2.1.25.2.1.4" 18/03/2014 12:24:33 (36 ms) : 1.3.6.1.2.1.25.2.3.1.2.38 = "1.3.6.1.2.1.25.2.1.4" 18/03/2014 12:24:33 (38 ms) : 1.3.6.1.2.1.25.2.3.1.3.1 = "Physical memory" 18/03/2014 12:24:33 (40 ms) : 1.3.6.1.2.1.25.2.3.1.3.3 = "Virtual memory" 18/03/2014 12:24:33 (43 ms) : 1.3.6.1.2.1.25.2.3.1.3.6 = "Memory buffers" 18/03/2014 12:24:33 (45 ms) : 1.3.6.1.2.1.25.2.3.1.3.7 = "Cached memory" 18/03/2014 12:24:33 (48 ms) : 1.3.6.1.2.1.25.2.3.1.3.10 = "Swap space" 18/03/2014 12:24:33 (50 ms) : 1.3.6.1.2.1.25.2.3.1.3.31 = "/" 18/03/2014 12:24:33 (53 ms) : 1.3.6.1.2.1.25.2.3.1.3.35 = "/dev/shm" 18/03/2014 12:24:33 (56 ms) : 1.3.6.1.2.1.25.2.3.1.3.36 = "/boot" 18/03/2014 12:24:33 (58 ms) : 1.3.6.1.2.1.25.2.3.1.3.37 = "/mnt/iaptus_docs" 18/03/2014 12:24:33 (61 ms) : 1.3.6.1.2.1.25.2.3.1.3.38 = "/mnt/iaptus_docs1" 18/03/2014 12:24:33 (64 ms) : 1.3.6.1.2.1.25.2.3.1.4.1 = "1024" 18/03/2014 12:24:33 (67 ms) : 1.3.6.1.2.1.25.2.3.1.4.3 = "1024" 18/03/2014 12:24:33 (70 ms) : 1.3.6.1.2.1.25.2.3.1.4.6 = "1024" 18/03/2014 12:24:33 (73 ms) : 1.3.6.1.2.1.25.2.3.1.4.7 = "1024" 18/03/2014 12:24:33 (78 ms) : 1.3.6.1.2.1.25.2.3.1.4.10 = "1024" 18/03/2014 12:24:33 (84 ms) : 1.3.6.1.2.1.25.2.3.1.4.31 = "4096" 18/03/2014 12:24:33 (89 ms) : 1.3.6.1.2.1.25.2.3.1.4.35 = "4096" 18/03/2014 12:24:33 (94 ms) : 1.3.6.1.2.1.25.2.3.1.4.36 = "1024" 18/03/2014 12:24:33 (99 ms) : 1.3.6.1.2.1.25.2.3.1.4.37 = "4096" 18/03/2014 12:24:33 (104 ms) : 1.3.6.1.2.1.25.2.3.1.4.38 = "4096" 18/03/2014 12:24:33 (109 ms) : 1.3.6.1.2.1.25.2.3.1.5.1 = "8194320" 18/03/2014 12:24:33 (114 ms) : 1.3.6.1.2.1.25.2.3.1.5.3 = "10258696" 18/03/2014 12:24:33 (119 ms) : 1.3.6.1.2.1.25.2.3.1.5.6 = "8194320" 18/03/2014 12:24:33 (125 ms) : 1.3.6.1.2.1.25.2.3.1.5.7 = "2302688" 18/03/2014 12:24:33 (130 ms) : 1.3.6.1.2.1.25.2.3.1.5.10 = "2064376" 18/03/2014 12:24:33 (135 ms) : 1.3.6.1.2.1.25.2.3.1.5.31 = "20007967" 18/03/2014 12:24:33 (140 ms) : 1.3.6.1.2.1.25.2.3.1.5.35 = "1007778" 18/03/2014 12:24:33 (144 ms) : 1.3.6.1.2.1.25.2.3.1.5.36 = "495844" 18/03/2014 12:24:33 (149 ms) : 1.3.6.1.2.1.25.2.3.1.5.37 = "193522614" 18/03/2014 12:24:33 (155 ms) : 1.3.6.1.2.1.25.2.3.1.5.38 = "38704122" 18/03/2014 12:24:33 (159 ms) : 1.3.6.1.2.1.25.2.3.1.6.1 = "6606492" 18/03/2014 12:24:33 (164 ms) : 1.3.6.1.2.1.25.2.3.1.6.3 = "6609700" 18/03/2014 12:24:33 (169 ms) : 1.3.6.1.2.1.25.2.3.1.6.6 = "321032" 18/03/2014 12:24:33 (175 ms) : 1.3.6.1.2.1.25.2.3.1.6.7 = "2302688" 18/03/2014 12:24:33 (180 ms) : 1.3.6.1.2.1.25.2.3.1.6.10 = "3208" 18/03/2014 12:24:33 (185 ms) : 1.3.6.1.2.1.25.2.3.1.6.31 = "5438832" 18/03/2014 12:24:33 (190 ms) : 1.3.6.1.2.1.25.2.3.1.6.35 = "0" 18/03/2014 12:24:33 (195 ms) : 1.3.6.1.2.1.25.2.3.1.6.36 = "63816" 18/03/2014 12:24:33 (200 ms) : 1.3.6.1.2.1.25.2.3.1.6.37 = "177591662" 18/03/2014 12:24:33 (204 ms) : 1.3.6.1.2.1.25.2.3.1.6.38 = "32608667"
Mar, 2014 - Permalink
Testing this out here, it looked like I was having a similar issue with the SNMP agent on one of the machines here but once I rebooted the Linux box, it seems to be working properly now. Can you please try rebooting the target?
If that doesn't work, please try creating a new sensor for this disk and let me know if you have the same issue.
Mar, 2014 - Permalink
Hi Greg,
I have tested a new sensor, but it still reports the wrong data. I cant get the server restarted as its used 24/7.
Any other help?
Mar, 2014 - Permalink
Would it be possible to restart the SNMP service on the server? Also, is this only happening on this one server or is it happening on multiple servers?
Mar, 2014 - Permalink
Hi Gerg,
I have just found time to have a look at this and found that the SNMP data is reported wrong, I have checked this using snmpwalk, df and PRTG. See the below table.
| df | df / 1024 | df * 1024 | PRTG | snmp | (snmp/1024)/1024 | |
|---|---|---|---|---|---|---|
| Total | 774090752.00 | 755948.00 | 792668930048.00 | 755948.00 | 792668626944.00 | 755947.71 |
| Available | 10838016.00 | 10584.00 | 11098128384.00 | 48913.00 | 51292991488.00 | 48916.81 |
| Used | 723931136.00 | 706964.00 | 741305483264.00 | 707035.00 | 741375635456.00 | 707030.90 |
To get an acurate view of the data I have used the SNMP Linux disk free sensor and added a line to the snmpd.conf file.
snmpd.conf: disk / 5%
This is all on Redhat 6 servers, will have a look at a CentOS server to see if I still get the same results.
Apr, 2014 - Permalink
This is an issue because of the way SNMP handles the values in 32bit counters. Please see: Why do my SNMP Disk Free sensors display incorrect or negative values?
Apr, 2016 - Permalink
What result do you get from the SNMP Tester? Would it be possible to post the output here of the tester along with the output of the df- h command in full?
Mar, 2014 - Permalink