When running under Fedora, issues may be seen with snmp values

[majed17]

this started happening in 1.2.18, i recall reading that it is a bug, so i waited for 1.2.20 but it is still present..
php 8.0.17
i'm on Fedora 35

2022/04/18 16:10:23 - CMDPHP PHP ERROR WARNING Backtrace:   (/host.php[141]:api_device_ping_device(),  /lib/api_device.php[1330]:cacti_snmp_session_get(),  /lib/snmp.php[497]:SNMP->get(), CactiErrorHandler())
--
2022/04/18 16:10:23 - ERROR PHP WARNING: SNMP::get(): Fatal error:  USM generic error in file: /usr/share/cacti/lib/snmp.php  on line: 497
2022/04/18 16:10:22 - CMDPHP PHP ERROR WARNING Backtrace:   (/var/lib/cacti/cli/poller_reindex_hosts.php[165]:run_data_query(),  /lib/data_query.php[106]:query_snmp_host(),  /lib/data_query.php[862]:cacti_snmp_session_get(),  /lib/snmp.php[497]:SNMP->get(), CactiErrorHandler())
2022/04/18 16:10:22 - ERROR PHP WARNING: SNMP::get(): Fatal error:  USM generic error in file: /usr/share/cacti/lib/snmp.php  on line: 497
2022/04/18 16:10:22 - CMDPHP PHP ERROR WARNING Backtrace:   (/var/lib/cacti/cli/poller_reindex_hosts.php[165]:run_data_query(),  /lib/data_query.php[106]:query_snmp_host(),  /lib/data_query.php[813]:cacti_snmp_session_walk(),  /lib/snmp.php[460]:SNMP->walk(), CactiErrorHandler())

[netniV]

     try {
          $out = @$session->get(trim($oid));
     } catch (Exception $e) {
          $out = false;
     }

That is what the code should look like there. Does it match yours?

[TheWitness]

I think we need to isolate this error in our snmp_ignore message list. Though a generic USM error speaks to something larger.

[majed17]

in /usr/share/cacti/lib/snmp.php on line: 497
i have:

try {
		$out = @$session->get(trim($oid));
	} catch (Exception $e) {
		$out = false;
	}

[TheWitness]

@majed17, please update lib/functions.php from the 1.2.x branch and report back.

[majed17]

that didn't solve the problem:

2022/04/20  09:51:25 - CMDPHP PHP ERROR WARNING Backtrace:   (/host.php[141]:api_device_ping_device(),  /lib/api_device.php[1330]:cacti_snmp_session_get(),  /lib/snmp.php[497]:SNMP->get(), CactiErrorHandler())
--
2022/04/20 09:51:25 - ERROR PHP WARNING: SNMP::get(): Fatal error:  USM generic error in file: /usr/share/cacti/lib/snmp.php  on line: 497
2022/04/20 09:51:24 - CMDPHP PHP ERROR WARNING Backtrace:   (/host.php[118]:host_reload_query(), /host.php[618]:run_data_query(),  /lib/data_query.php[106]:query_snmp_host(),  /lib/data_query.php[862]:cacti_snmp_session_get(),  /lib/snmp.php[497]:SNMP->get(), CactiErrorHandler())
2022/04/20 09:51:24 - ERROR PHP WARNING: SNMP::get(): Fatal error:  USM generic error in file: /usr/share/cacti/lib/snmp.php  on line: 497
2022/04/20 09:51:24 - CMDPHP PHP ERROR WARNING Backtrace:   (/host.php[118]:host_reload_query(), /host.php[618]:run_data_query(),  /lib/data_query.php[106]:query_snmp_host(),  /lib/data_query.php[813]:cacti_snmp_session_walk(),  /lib/snmp.php[460]:SNMP->walk(), CactiErrorHandler())
2022/04/20 09:51:24 - ERROR PHP WARNING: SNMP::walk(): Fatal error:  USM generic error in file: /usr/share/cacti/lib/snmp.php  on line: 460
2022/04/20 09:51:24 - CMDPHP PHP ERROR WARNING Backtrace:   (/host.php[118]:host_reload_query(), /host.php[618]:run_data_query(),  /lib/data_query.php[106]:query_snmp_host(),  /lib/data_query.php[813]:cacti_snmp_session_walk(),  /lib/snmp.php[460]:SNMP->walk(), CactiErrorHandler())
2022/04/20 09:51:24 - ERROR PHP WARNING: SNMP::walk(): Fatal error:  USM generic error in file: /usr/share/cacti/lib/snmp.php  on line: 460
2022/04/20 09:51:24 - CMDPHP PHP ERROR WARNING Backtrace:   (/host.php[118]:host_reload_query(), /host.php[618]:run_data_query(),  /lib/data_query.php[106]:query_snmp_host(),  /lib/data_query.php[813]:cacti_snmp_session_walk(),  /lib/snmp.php[460]:SNMP->walk(), CactiErrorHandler())
2022/04/20 09:51:24 - ERROR PHP WARNING: SNMP::walk(): Fatal error:  USM generic error in file: /usr/share/cacti/lib/snmp.php  on line: 460
2022/04/20 09:51:23 - CMDPHP PHP ERROR WARNING Backtrace:   (/host.php[118]:host_reload_query(), /host.php[618]:run_data_query(),  /lib/data_query.php[106]:query_snmp_host(),  /lib/data_query.php[813]:cacti_snmp_session_walk(),  /lib/snmp.php[460]:SNMP->walk(), CactiErrorHandler())
2022/04/20 09:51:23 - ERROR PHP WARNING: SNMP::walk(): Fatal error:  USM generic error in file: /usr/share/cacti/lib/snmp.php  on line: 460
2022/04/20 09:51:23 - CMDPHP PHP ERROR WARNING Backtrace:   (/host.php[118]:host_reload_query(), /host.php[618]:run_data_query(),  /lib/data_query.php[106]:query_snmp_host(),  /lib/data_query.php[813]:cacti_snmp_session_walk(),  /lib/snmp.php[460]:SNMP->walk(), CactiErrorHandler())
2022/04/20 09:51:23 - ERROR PHP WARNING: SNMP::walk(): Fatal error:  USM generic error in file: /usr/share/cacti/lib/snmp.php  on line: 460
2022/04/20 09:51:15 - CMDPHP PHP ERROR WARNING Backtrace:   (/host.php[141]:api_device_ping_device(),  /lib/api_device.php[1330]:cacti_snmp_session_get(),  /lib/snmp.php[497]:SNMP->get(), CactiErrorHandler())
2022/04/20 09:51:15 - ERROR PHP WARNING: SNMP::get(): Fatal error:  USM generic error in file: /usr/share/cacti/lib/snmp.php  on line: 497
2022/04/20 09:48:53 - CMDPHP PHP ERROR WARNING Backtrace:   (/host.php[141]:api_device_ping_device(),  /lib/api_device.php[1330]:cacti_snmp_session_get(),  /lib/snmp.php[497]:SNMP->get(), CactiErrorHandler())
2022/04/20 09:48:53 - ERROR PHP WARNING: SNMP::get(): Fatal error:  USM generic error in file: /usr/share/cacti/lib/snmp.php  on line: 497

[TheWitness]

Okay, add a Cacti log to the trimmed OID and let's see which ones cause the errors;

cacti_log("The OID is '$oid'", false, 'SNMP');

Then let's try to track down the host. It's not going to be entirely easy.

[majed17]

where to add it?

[TheWitness]

Just before line 497. Review your log.

[TheWitness]

And line 460.

[majed17]

ok

2022/04/20  15:29:20 - CMDPHP PHP ERROR WARNING Backtrace:   (/host.php[141]:api_device_ping_device(),  /lib/api_device.php[1330]:cacti_snmp_session_get(),  /lib/snmp.php[499]:SNMP->get(), CactiErrorHandler())
--
2022/04/20 15:29:20 - ERROR PHP WARNING: SNMP::get(): Fatal error:  USM generic error in file: /usr/share/cacti/lib/snmp.php  on line: 499
2022/04/20 15:29:20 - SNMP The OID is '.1.3.6.1.2.1.1.1.0'

[netniV]

That's a fairly generic OID, suggests that maybe the SNMP details aren't correct, You can find out the host using $session->hostname but the problem you will have is that this is a private variable (at least if using the phpsnmp class that we include). You could have use the info variable but that is also useless as it's not being primed in the current version.

Your best bet is to dump the session var using var_export($session, true) to a log and see if it includes those private variables to help you track the host down.

[netniV]

If you want a fix for that, btw, edit the include/phpsnmp/classSNMP.php and change the $info variable to $this->info at the end of the __construct function. Then you'll be able to use $session->info to see the host details without using var_export.