Hey,
After migrating switches from SNMPv2c to SNMPv3, Centreon stopped collecting SNMP data from Dell S4048-ON devices (OS10 Enterprise 10.5.2.2). The same SNMPv3 configuration works perfectly on Cisco Catalyst 9200 switches, but on Dell OS10 devices Centreon consistently returns:UNKNOWN: Can't construct cache...
SNMP library / plugin used:/usr/lib/centreon/plugins/centreon_cisco_standard_snmp.pl --plugin=network::cisco::standard::snmp::plugin --mode=interfaces
Test command executed on Centreon host:
/usr/lib/centreon/plugins/centreon_cisco_standard_snmp.pl \ --plugin=network::cisco::standard::snmp::plugin \ --mode=interfaces \ --hostname=10.81.224.12 \ --snmp-version=3 \ --snmp-username='fnsp_snmp' \ --authprotocol='sha' \ --authpassphrase='***' \ --privprotocol='aes' \ --privpassphrase='***' 
Output:UNKNOWN: Can't construct cache...
Manual SNMPv3 test via snmpwalk:
snmpwalk -v3 -l authPriv -u fnsp_snmp \ -a SHA -A '***' \ -x AES -X '***' \ 10.81.224.12 1.3.6.1.2.1.1 
Result:iso.3.6.1.2.1.1 = No more variables left in this MIB View (It is past the end of the MIB tree)
Same result for:
snmpwalk -v3 -l authPriv -u fnsp_snmp \ -a SHA -A '***' \ -x AES -X '***' \ 10.81.224.12 1.3.6.1.2.1.2.2.1.2 
Dell S4048 (OS10 Enterprise 10.5.2.2) SNMP configuration:
snmp-server view ALL iso included snmp-server group SNMPv3Group v3 priv read ALL snmp-server user fnsp_snmp SNMPv3Group v3 auth sha *** priv aes *** show snmp group show snmp user 
Output:
groupname : SNMPv3Group version : 3 security level : priv readview : ALL User name : fnsp_snmp Group : SNMPv3Group Version : 3 Authentication Protocol : SHA Privacy Protocol : AES 
Centreon cache check:
Cache files located in /var/lib/centreon/centplugins/.
For working devices, cache size is typically 20–80 KB.
For the affected host (10.81.224.12), cache size was only 29 bytes:
snmpstandard_10.81.224.12_161_interfaces_*.cache 
Steps already tried:
- 	Deleted all cache files: rm -f /var/lib/centreon/centplugins/*10.81.224.12* rm -f /tmp/centreon/*10.81.224.12*
- 	Restarted Centreon poller: systemctl restart cbd centengine gorgoned
- 	Retested with same command – issue persists. 
- 	Confirmed Dell SNMPv3 authentication and encryption works via snmpwalk. 
- 	Reconfigured SNMPv3 user, group, and view on Dell switch. 
- 	Verified readview ALLand correct security level.
- 	Other Dell switches running OS10 show the same behavior. 
- 	Cisco Catalyst 9200 with identical SNMPv3 settings works correctly. 
- 	Dell OS10 always responds: No more variables left in this MIB View.
Expected result:
Centreon plugin should retrieve IF-MIB data (interfaces) and construct the SNMP cache as it does on Cisco devices.
Actual result:
Centreon returns UNKNOWN: Can't construct cache... and creates an empty or incomplete cache file (~29 B).
Question for Centreon Support:
Is there any known issue with SNMPv3 handling for Dell OS10 (S4048) devices using the network::cisco::standard::snmp::plugin?
Does this plugin fully support Dell OS10 SNMPv3 responses?
Is there a workaround (for example a different OID, MIB view definition, or forcing IF-MIB mode)?
Summary:
- 	SNMPv3 (SHA/AES, authPriv) confirmed working. 
- 	Centreon plugin fails to build SNMP cache only for Dell OS10 switches. 
- 	Works fine on Cisco Catalyst 9200 with the same configuration. 
- 	Issue appeared immediately after migrating from SNMPv2c to SNMPv3. 
