It still works I think - I added the ability to list all the interfaces if you…

It still works I think - I added the ability to list all the interfaces if you just omit the '-i' argument, example:

[jrdalrymple@mn-lx9 pf_interface_usage]$ ./check_snmp_usage.py -H 192.168.0.1
No interface specified - here are your options:
pflow0
vlan301
vlan300
vlan1
vlan202
pflog0
vlan204
vlan200
vlan201
lo0
vlan203
enc0
em0
em3
em2
em1
vlan105
pppoe0
pflow1

check_snmp_usage.py

@@ -55,6 +55,37 @@ unitMultipliers = {	'b' : 1,
 
 limitMatch = re.compile(r"([0-9]+)([bBkKmMgGtT]{0,1})")
 
+# Find snmpwalk and snmpget
+
+sp = subprocess.Popen(['which', 'snmpget'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+stdout, stderr = sp.communicate()
+if sp.returncode == 0:
+	snmpget = stdout.rstrip()
+else:
+	print('I couldn\'t find snmpget on your system, unable to finish')
+	sys.exit(3)
+
+sp = subprocess.Popen(['which', 'snmpwalk'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+stdout, stderr = sp.communicate()
+if sp.returncode == 0:
+	snmpwalk = stdout.rstrip()
+else:
+	print('I couldn\'t find snmpwalk on your system, unable to finish')
+	sys.exit(3)
+
+
+# Functions
+def getInterfaces():
+	interfaceDict = {}
+	walkIfsCmd = [snmpwalk, '-v2c', '-c', communityString, host, OIDIfDescr]
+	sp = subprocess.Popen(walkIfsCmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+	stdout, stderr = sp.communicate()
+	walkOut = stdout.rstrip().split('\n')
+	for line in walkOut:
+		interfaceDict[line.split()[-1]] = line.split()[0].split('.')[-1]
+	return interfaceDict
+	
+
 #USAGE
 def usage():
         print('Usage: check_snmp_usage.py -H hostname -i interface -b bandwidth limit (bytes) -c community string \n')
@@ -86,6 +117,13 @@ if not 'host' in locals():
         print('No host specified')
         sys.exit(3)
 
+if not 'interface' in locals():
+	interfaceDict = getInterfaces()
+	print('No interface specified - here are your options:')
+	for interface in interfaceDict:
+		print(interface)
+	sys.exit(3)
+
 if not 'bytesLimit' in locals():
 	bytesLimit = 0
 if not limitMatch.match(bytesLimit):
@@ -96,39 +134,10 @@ else:
 	if multiplier:
 		bytesLimit = int(scalar) * int(unitMultipliers[multiplier])
 
-# Find snmpwalk and snmpget
-
-sp = subprocess.Popen(['which', 'snmpget'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-stdout, stderr = sp.communicate()
-if sp.returncode == 0:
-	snmpget = stdout.rstrip()
-else:
-	print('I couldn\'t find snmpget on your system, unable to finish')
-	sys.exit(3)
-
-sp = subprocess.Popen(['which', 'snmpwalk'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-stdout, stderr = sp.communicate()
-if sp.returncode == 0:
-	snmpwalk = stdout.rstrip()
-else:
-	print('I couldn\'t find snmpwalk on your system, unable to finish')
-	sys.exit(3)
 
 
-
-# Start by getting the list of available interfaces
-
-walkIfsCmd = [snmpwalk, '-v2c', '-c', communityString, host, OIDIfDescr]
-sp = subprocess.Popen(walkIfsCmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-stdout, stderr = sp.communicate()
-walkOut = stdout.rstrip().split('\n')
-for line in walkOut:
-	if line.split()[-1] == interface:
-		index = line.split()[0].split('.')[-1]
-
-if not 'index' in locals():
-	print('No matching interfaces found!')
-	sys.exit(3)
+# Not optimized - we'll be getting all of the interfaces from the remote system and match up the indexes
+interfaceDict = getInterfaces()
 
 # Now let's grab our counters and the date of the remote system
 
@@ -146,8 +155,8 @@ current['hour'] = time.split(':')[0]
 current['minute'] = time.split(':')[1]
 current['second'] = time.split(':')[2].split('.')[0]
 
-getInBytesCmd = [snmpget, '-v2c', '-c', communityString, host, OIDIfInBytes + index]
-getOutBytesCmd = [snmpget, '-v2c', '-c', communityString, host, OIDIfOutBytes + index]
+getInBytesCmd = [snmpget, '-v2c', '-c', communityString, host, OIDIfInBytes + interfaceDict[interface]]
+getOutBytesCmd = [snmpget, '-v2c', '-c', communityString, host, OIDIfOutBytes + interfaceDict[interface]]
 
 sp = subprocess.Popen(getInBytesCmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
 stdout, stderr = sp.communicate()