[ZBXNEXT-6554] Zabbix Agent Remote Execution limit to 512kb Created: 2021 Mar 10  Updated: 2025 May 04  Resolved: 2023 Sep 24

Status: Closed
Project: ZABBIX FEATURE REQUESTS
Component/s: Agent (G)
Affects Version/s: 5.0.9
Fix Version/s: 6.0.22rc1, 6.4.7rc1, 7.0.0alpha5, 7.0 (plan)

Type: Change Request Priority: Medium
Reporter: Dimitri Bellini Assignee: Dmitrijs Goloscapovs (Inactive)
Resolution: Fixed Votes: 6
Labels: agent, remotecommands
Remaining Estimate: Not Specified
Time Spent: Not Specified
Original Estimate: Not Specified
Environment:

RHEL 6.x/RHEL 7.x

Attachments: PNG File Screenshot 2023-08-09 at 13.23.38.png    
Issue Links:
Causes
causes ZBXNEXT-8682 Item test should limit the returned v... Closed
Duplicate
is duplicated by ZBXNEXT-5494 Increase custom LLD data user paramet... Closed
Sub-task
part of ZBXNEXT-6233 Pick up bigger text file than 64K, vf... Closed
Epic Link: Zabbix 7.0
Team: Team A
Sprint: Sprint 103 (Aug 2023), Sprint 104 (Sep 2023)
Story Points: 0.125

 Description   

In big Enterprise machines a simple system.run like "ps -ef" could be very large (more than 1.5MB) and exceed the limit of the Zabbix Agent output of 512KB.

Please increase this limit.

Thanks

 Comments   
Comment by Nathan Liefting [ 2023 Aug 09 ]

This issue is also present with UserParameters. 512KB is way too small as a size limit, this should be increased.

Comment by Alex Kalimulin [ 2023 Aug 10 ]

We should change MAX_EXECUTE_OUTPUT_LEN to 16MB. This will affect the max output size of:

  • system.run, user parameters and remote scripts on the agent
  • some agent output that uses external commands (e.g. system.sw.packages)
  • scripts on server and proxy
  • alert scripts on server (output unused?)
  • external checks
  • SSH checks

Components involved: Agent, Agent2 (look for MaxExecuteOutputLenB), Server and Proxy.
Compatibility between versions built with different limits should be also taken into account (e.g. old proxy and new server, etc; it should be okay, but still).

We should also document this change:

  • Change 512KB -> 16MB where this limit is mentioned (e.g. in user parameters)
  • Add a note about the limit where it's not currently documented (e.g. in SSH checks)
Comment by Alex Kalimulin [ 2023 Aug 23 ]

To avoid ugly workarounds with system.run we will also increase vfs.file.contents to 16MB.

Comment by Dmitrijs Goloscapovs (Inactive) [ 2023 Sep 08 ]

Available in versions:
  - pre-6.0.22rc1 - 43106ad9ce2
  - pre-6.4.7rc1 - a070e1b7e53
  - pre-7.0.0alpha5 - 8334785bb3f

Comment by Nathan Liefting [ 2023 Sep 11 ]

Amazing! Thanks for the quick response and fix on this.

Comment by Arturs Dancis [ 2023 Sep 19 ]

Documentation updated:

  • Configuration > User parameters (6.0, 6.4, 7.0)
  • Configuration > Notifications upon events > Actions > Operations > Remote commands (6.0, 6.4, 7.0)
  • Discovery > Low-level discovery (6.4), > Custom LLD rules (6.0, 7.0)
  • Discovery > Low-level discovery > Notes on low-level discovery (6.0, 6.4, 7.0)
  • Web interface > Frontend sections > Administration > Scripts (6.0)
  • Web interface > Frontend sections > Alerts > Scripts (6.4, 7.0)
  • Appendixes > Process configuration:
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