[snmp_facts] separate system description query

- snmp cpu test consistently fails on s6000 with default timeout.
- System description takes more than 1 seconds in snmp cpu test
  (when all cores are pined at 100% busy).
- Give this query its own timeout (5 seconds).

Author: yxieca

ansible/library/snmp_facts.py

@@ -290,10 +290,26 @@ def main():
 
     results = Tree()
 
+    # Getting system description could take more than 1 second on some Dell platform
+    # (e.g. S6000), increse timeout to tolerate the delay.
     errorIndication, errorStatus, errorIndex, varBinds = cmdGen.getCmd(
         snmp_auth,
-        cmdgen.UdpTransportTarget((m_args['host'], 161)),
+        cmdgen.UdpTransportTarget((m_args['host'], 161), timeout=5.0),
         cmdgen.MibVariable(p.sysDescr,),
+    )
+
+    if errorIndication:
+        module.fail_json(msg=str(errorIndication) + ' querying system description.')
+
+    for oid, val in varBinds:
+        current_oid = oid.prettyPrint()
+        current_val = val.prettyPrint()
+        if current_oid == v.sysDescr:
+            results['ansible_sysdescr'] = decode_hex(current_val)
+
+    errorIndication, errorStatus, errorIndex, varBinds = cmdGen.getCmd(
+        snmp_auth,
+        cmdgen.UdpTransportTarget((m_args['host'], 161)),
         cmdgen.MibVariable(p.sysObjectId,),
         cmdgen.MibVariable(p.sysUpTime,),
         cmdgen.MibVariable(p.sysContact,),
@@ -307,9 +323,7 @@ def main():
     for oid, val in varBinds:
         current_oid = oid.prettyPrint()
         current_val = val.prettyPrint()
-        if current_oid == v.sysDescr:
-            results['ansible_sysdescr'] = decode_hex(current_val)
-        elif current_oid == v.sysObjectId:
+        if current_oid == v.sysObjectId:
             results['ansible_sysobjectid'] = current_val
         elif current_oid == v.sysUpTime:
             results['ansible_sysuptime'] = current_val