用python easysnmp捕获异常

Question

I cannot seem to find documentation or examples of how to catch exceptions with Python's easySNMP library

https://easysnmp.readthedocs.io/en/latest/exceptions.html shows what exceptions are rasied but I get errors when trying to catch them

Simplified code:

from easysnmp import Session
try:
    session = Session(hostname=host,community=community, version=2)
except:
    print("ERROR - SNMP error:")
    sys.exit(3)    

def check_snmp(oid):
    try:
        ret = session.get(oid).value
    except easysnmp.EasySNMPNoSuchInstanceError:
        ## Return false if OID doesn't exists
        return 0
    except session.EasySNMPError as e:
        ## Print the error on general errors
        print("ERROR - SNMP error: {}".format(e))
    return 1

if check_snnp('ifalias.4'):
    print("SNMP returned true")

Output:

Traceback (most recent call last):
    File "./check_ip_route", line 72, in <module>
    if check_snmp(oid):
    File "./check_snmp", line 45, in check_snmp
        except easysnmp.EasySNMPNoSuchInstanceError:
    NameError: name 'easysnmp' is not defined

Answer 1

Your error says name 'easysnmp' is not defined.

That is because you haven't imported it.

Instead you imported from easysnmp import Session

you need to do import easysnmp