Description:
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I have a network discovery application that takes an array of credentials and tests they work against SNMP devices. In this case, SNMPv3 devices. 

If I connect using a valid SNMPv3 credential set first in the array, things work as expected. 

If I connect using a bad set first in the array, the connection fails, as expected. 

If I connect using a valid SNMPv3 credential set second in the array (after the prior bad set), it fails.

This only seems to occur when using identical Security Names, but having otherwise different attributes.

Even if I unset the SNMP object in the loop each time, subsequent attempts to connect using valid credentials fail (as per above).

Test script:
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Same code in SO question here - 

https://stackoverflow.com/questions/69491850/php-snmpv3-credentials-test-loop-failing

Expected result:
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Should be able to connect using differing credentials after the object is unset, but even better if the object doesn't need unsetting.