1. SNMP Terms SNMP Agent (network element to monitor) SNMP Management Station Community String (password) SMI (Structure of Management Info) MIB (Management Information Base) ASN.1 (Abstract Syntax Notation 1)

2. ASN.1 - Abstract Syntax Notation SNMP uses a subset of ASN.1 datatypes –Integer, Octet, String, Object Identifier, Sequence, Null Basic encoding rules compile language into sequence of octets Lexographic ordering allows agent to answer requests without knowing data object size

3. SNMP Control Flow Management Station Polls Agent –Typically every 5 minutes Agent Sends Unsolicited SNMP Traps –Agent alerts management station as needed

4. Agent Commands set-request –Set a variable or cause an action, need Read/Write access get-request –Fetch a data object get-next-request –Walk through a table get-bulk-request –Get in bulk for efficiency

5. Data Object Naming Naming hierarchy uses numbers or names, relative or absolute naming –system.sysDescr.0 –1.1.0 –1.sysDescr.0 –.1.3.6.1.2.1.1.0 –.iso.org.dod.internet.mgmt.mib.system.sysdescr.0 –.1.3.6.1.2.1.1.sysdescr.0

6. MIB Tree

7. MIB Tree (Cont) mgmt(2)

8. Command Line Tools –snmpget –snmpwalk –snmpset –snmpnetstat GUI Tools –MRTG, Cricket, HP Openview, WhatsUpGold

9. SNMP Router Syntax access-list 10 permit 172.20.0.0 0.0.255.255 access-list 10 permit 192.168.0.0 0.0.255.255 snmp-server community public RO snmp-server community private RW 10 snmp-server location 16LOV snmp-server contact Ray Curci snmp-server chassis-id Chassis-ID-Goes-Here snmp-server system-shutdown

10. Snmpset iso(1) org(3) dod(6) internet(1) private(4) enterprises(1) cisco(9) local(2) lts(9) 9 nothing(1), reload(2), messagedone(3), abort(4) S1> snmpset 172.20.11.1 private.1.3.6.1.4.1.9.2.9.9.0 i 2 ****** --- SHUTDOWN NOW --- *** Message from network to all terminals: *%SYS-5-RELOAD: Reload requested

11. Snmpget S1> snmpget 172.20.11.1 public system.sysDescr.0 system.sysDescr.0 = Cisco Internetwork Operating System Software IOS (tm) 3000 Software (IGS-DR-L), Version 11.0(11 Copyright (c) 1986-1996 by cisco Systems, Inc. Compiled Mon 16-Sep-96 18:44 by athavale

12. Snmpwalk S1> snmpwalk 172.20.11.1 public system system.sysDescr.0 = Cisco IOS 11.0(11)... system.sysUpTime.0 = Timeticks: (168468) 0:28:04.68 system.sysContact.0 = Ray Curci system.sysName.0 = r1 system.sysLocation.0 = 16LOV

13. Snmpnetstat - routing table S1> snmpnetstat 192.168.11.1 public -rn Routing tables Destination Gateway Flags Interface default 192.168.16.6 UG Serial1/6 172.20 192.168.16.6 UG Serial1/6 192.168.1 192.168.1.1 U Fddi0/0 …

14. Snmpget -interface stats S1> snmpnetstat 192.168.11.1 public -i Name Mtu Address Ipkts Ierrs Opkts Fddi0/0 4470 192.168.1.1 241743 2 101101 Ethernet2/0 1500 192.168.10.1 151077 0 174792 …

15. Multi Router Traffic Grapher FSU Network Graphs –http://mrtg.acns.fsu.edu/mrtg/ MRTG Software Page –http://people.ee.ethz.ch/~oetiker/webtools/mrtg/

16. Additional SNMP Resources The Simple Book 2/e, by Marshall Rose Network Management-Problems,Standards,Strategies by Kauffels –http://mrtg.acns.fsu.edu/mrtg/ Network Monitoring Explained-Design and Application by Chiu and Sudama Cisco SNMP Technical Tips –http://www.cisco.com/warp/public/477/SNMP/index.html SNMP Overview - Rad Data Comm –http://www.rad.com/networks/1995/snmp/snmp.htm