[ZBX-20869] Item: vfs.file.contents["/sys/class/net/IF/speed"] unsupported on some systems Created: 2022 Apr 08  Updated: 2026 Jan 16

Status: Confirmed
Project: ZABBIX BUGS AND ISSUES
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Problem report Priority: Trivial
Reporter: Nathan Liefting Assignee: Denis Rasikhov (Inactive)
Resolution: Unresolved Votes: 10
Labels: preprocessing, templates
Remaining Estimate: Not Specified
Time Spent: 6h
Original Estimate: Not Specified

Attachments: PNG File image-2022-04-08-10-11-56-423.png    
Issue Links:
Related
related to ZBXNEXT-2286 net.if.discovery filtration Open
related to ZBXNEXT-5367 Extend net.if metrics on Linux using ... Open
related to ZBXNEXT-7502 Add new network discovery item net.if... Needs documenting
related to ZBX-25960 Interface speeds for down interface n... Confirmed
related to ZBXNEXT-10156 Add interface speed overrides for Lin... Need info
related to ZBX-21697 Linux reports wrong speed for vnet de... Confirmed
related to ZBX-24442 zabbix agent overwhelms its log file ... Confirmed
related to ZBX-24057 Reporting speed for wlanX fails Confirmed

 Description   

Hi Zabbix support,

 

Seems like the default Linux interface discovery template has a small issue. Some systems might give back their interface speed item as a negative value. Seems like this means it cannot be detected and it throws an error:

I think it's a discussion wether or not the unsupported item is fine like this, but it seems cleaner to use a pre-processing step "Check for not supported values"

Related ticket: ZBXNEXT-6784

Regards,
Nathan

 

 Comments   
Comment by Ignacio Facundo Aguirre [ 2022 Nov 09 ]

Hi, I'm having the same issue, the content of the file /sys/class/net/eth0/speed is -1 in all the VMs. Some short and good info about it.

Comment by Orion Poplawski [ 2025 Feb 21 ]

Similar issue, with the status toggling:

{{389222:20250221:082312.593 item "HOST:vfs.file.contents["/sys/class/net/enp1s0/speed"]" became not supported: Value of type "string" is not suitable for value type "Numeric (unsigned)". Value "-1000000" }}
{{389222:20250221:082658.569 item "HOST:vfs.file.contents["/sys/class/net/enp1s0/speed"]" became supported }}
389222:20250221:092657.787 item "HOST:vfs.file.contents["/sys/class/net/enp1s0/speed"]" became not supported: Value of type "string" is not suitable for value type "Numeric (unsigned)". Value "-1000000"

Comment by Tristis Oris [ 2025 Feb 25 ]

got this on every ubuntu 18-24.

check 'vfs.file.contents["/sys/class/net/enX0/speed"]' is not supported: Cannot read from file: read /sys/class/net/enX0/speed: invalid argument

Comment by Harri [ 2026 Jan 16 ]

I have this problem all over the place. Sample:

root@node09b:~# cat /sys/class/net/*/speed 
10000
10000
10000
10000
cat: /sys/class/net/eno12419/speed: Invalid argument
cat: /sys/class/net/eno12429/speed: Invalid argument
1000
cat: /sys/class/net/eno8403/speed: Invalid argument
cat: /sys/class/net/ens7f0/speed: Invalid argument
cat: /sys/class/net/ens7f1/speed: Invalid argument
cat: /sys/class/net/lo/speed: Invalid argument
-1
10000
10000
10000
10000
10000
10000
10000
10000

As a result zabbix_agent2.log is flooded with errors:

2026/01/16 08:17:16.001146 check 'vfs.file.contents["/sys/class/net/eno12419/speed"]' is not supported: Cannot read from file: read /sys/class/net/eno12419/speed: invalid argument
2026/01/16 08:17:17.001601 check 'vfs.file.contents["/sys/class/net/eno12429/speed"]' is not supported: Cannot read from file: read /sys/class/net/eno12429/speed: invalid argument
2026/01/16 08:17:18.001044 check 'vfs.file.contents["/sys/class/net/ens7f0/speed"]' is not supported: Cannot read from file: read /sys/class/net/ens7f0/speed: invalid argument
2026/01/16 08:17:19.001046 check 'vfs.file.contents["/sys/class/net/ens7f1/speed"]' is not supported: Cannot read from file: read /sys/class/net/ens7f1/speed: invalid argument
2026/01/16 08:22:15.000996 check 'vfs.file.contents["/sys/class/net/eno8403/speed"]' is not supported: Cannot read from file: read /sys/class/net/eno8403/speed: invalid argument
2026/01/16 08:22:16.000913 check 'vfs.file.contents["/sys/class/net/eno12419/speed"]' is not supported: Cannot read from file: read /sys/class/net/eno12419/speed: invalid argument
2026/01/16 08:22:17.000947 check 'vfs.file.contents["/sys/class/net/eno12429/speed"]' is not supported: Cannot read from file: read /sys/class/net/eno12429/speed: invalid argument
2026/01/16 08:22:18.001510 check 'vfs.file.contents["/sys/class/net/ens7f0/speed"]' is not supported: Cannot read from file: read /sys/class/net/ens7f0/speed: invalid argument
2026/01/16 08:22:19.001247 check 'vfs.file.contents["/sys/class/net/ens7f1/speed"]' is not supported: Cannot read from file: read /sys/class/net/ens7f1/speed: invalid argument
2026/01/16 08:27:15.000812 check 'vfs.file.contents["/sys/class/net/eno8403/speed"]' is not supported: Cannot read from file: read /sys/class/net/eno8403/speed: invalid argument
2026/01/16 08:27:16.001418 check 'vfs.file.contents["/sys/class/net/eno12419/speed"]' is not supported: Cannot read from file: read /sys/class/net/eno12419/speed: invalid argument
2026/01/16 08:27:17.000587 check 'vfs.file.contents["/sys/class/net/eno12429/speed"]' is not supported: Cannot read from file: read /sys/class/net/eno12429/speed: invalid argument
2026/01/16 08:27:18.000891 check 'vfs.file.contents["/sys/class/net/ens7f0/speed"]' is not supported: Cannot read from file: read /sys/class/net/ens7f0/speed: invalid argument
2026/01/16 08:27:19.000889 check 'vfs.file.contents["/sys/class/net/ens7f1/speed"]' is not supported: Cannot read from file: read /sys/class/net/ens7f1/speed: invalid argument
2026/01/16 08:32:15.001277 check 'vfs.file.contents["/sys/class/net/eno8403/speed"]' is not supported: Cannot read from file: read /sys/class/net/eno8403/speed: invalid argument
2026/01/16 08:32:16.000951 check 'vfs.file.contents["/sys/class/net/eno12419/speed"]' is not supported: Cannot read from file: read /sys/class/net/eno12419/speed: invalid argument
2026/01/16 08:32:17.001439 check 'vfs.file.contents["/sys/class/net/eno12429/speed"]' is not supported: Cannot read from file: read /sys/class/net/eno12429/speed: invalid argument
2026/01/16 08:32:18.001776 check 'vfs.file.contents["/sys/class/net/ens7f0/speed"]' is not supported: Cannot read from file: read /sys/class/net/ens7f0/speed: invalid argument
2026/01/16 08:32:19.001620 check 'vfs.file.contents["/sys/class/net/ens7f1/speed"]' is not supported: Cannot read from file: read /sys/class/net/ens7f1/speed: invalid argument
2026/01/16 08:37:15.001058 check 'vfs.file.contents["/sys/class/net/eno8403/speed"]' is not supported: Cannot read from file: read /sys/class/net/eno8403/speed: invalid argument
2026/01/16 08:37:16.000734 check 'vfs.file.contents["/sys/class/net/eno12419/speed"]' is not supported: Cannot read from file: read /sys/class/net/eno12419/speed: invalid argument
2026/01/16 08:37:17.000771 check 'vfs.file.contents["/sys/class/net/eno12429/speed"]' is not supported: Cannot read from file: read /sys/class/net/eno12429/speed: invalid argument
2026/01/16 08:37:18.000891 check 'vfs.file.contents["/sys/class/net/ens7f0/speed"]' is not supported: Cannot read from file: read /sys/class/net/ens7f0/speed: invalid argument
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