SNMP Management: Management Information Base by Behzad Akbari Fall 2008 In the Name of the Most High

MIB  Used to group related objects together  Facilitates logical assignment of object identifiers  That will be the way the objects are stored and accessed  Not to be mistaken with aggregate object type  MIB-II (RFC 1213) is superset of MIB-I  Objects that are related grouped into object groups  MIB module comprises module name, imports from other modules, and definitions of current module  RFC 1213 defines eleven groups

MIB II (RFC 1213) System Group  Provide general information about the managed system. Interfaces Group  Contains generic information about the physical interfaces. Address-Translation Group  Contains information about the mapping between network addresses and physical addresses for each physical interface. IP Group  Contains information about the implementation and operation of IP at the managed system. ICMP Group  Contains information about the implementation and operation of ICMP at the managed system.

MIB-II (cont.) TCP Group  Contains information about the implementation and operation of TCP at the managed system. UDP Group  Contains information about the implementation and operation of UDP at the managed system. EGP Group  Contains information about the implementation and operation of EGP at the managed system. CMOT Group  Placeholder for OSI (CMIP Over TCP/IP) Transmission Group  Provides details about the underlying transmission media for each interface. SNMP Group  Provides the statistics of SNMP operations at the managed system.

MIB-2 OBJECT IDENTIFIER {mgmt 1}

System Group

sysServices OBJECT-TYPE SYNTAX INTEGER (0..127) ACCESS read-only STATUS mandatory DESCRIPTION "A value which indicates the set of services that this entity primarily offers. The value is a sum. This sum initially takes the value zero, Then, for each layer, L, in the range 1 through 7, that this node performs transactions for, 2 raised to (L - 1) is added to the sum. For example, a node which performs primarily routing functions would have a value of 4 (2^(3-1)). In contrast, a node which is a host offering application services would have a value of 72 (2^(4-1) + 2^(7-1)). Note that in the context of the Internet suite of protocols, values should be calculated accordingly: layer functionality 1 physical (e.g., repeaters) 2 datalink/subnetwork (e.g., bridges) 3 internet (e.g., IP gateways) 4 end-to-end (e.g., IP hosts) 7 applications (e.g., mail relays) For systems including OSI protocols, layers 5 and 6 may also be counted." ::= { system 7 } 72=

Interfaces Group

iFEntry

ifType

ifAdminStatus OBJECT-TYPE SYNTAX INTEGER { up(1), -- ready to pass packets down(2), testing(3) -- in some test mode } ACCESS read-write STATUS mandatory DESCRIPTION "The desired state of the interface. The testing(3) state indicates that no operational packets can be passed." ::= { ifEntry 7 } ifOperStatus OBJECT-TYPE SYNTAX INTEGER { up(1), -- ready to pass packets down(2), testing(3) -- in some test mode } ACCESS read-only STATUS mandatory DESCRIPTION "The current operational state of the interface. The testing(3) state indicates that no operational packets can be passed." ::= { ifEntry 8 }

ifTable

ifTable (cont.)

IP Group

ipForwarding: forwarding(1) not-forwarding(2) IP Address Table contains table of IP addresses IP Route Table contains an entry for each route IP Network-to-Media Table is address translation table mapping IP addresses to physical addresses

IP Address Table

ipAddrTable

IP Routing Table

ipRouteTable Example other(1), invalid(2), direct(3), indirect(4) other(1), local(2), netmgmt(3), icmp(4), egp(5), ggp(6), hello(7), rip(8), is-is(9), s-is(10), ciscoIgrp(11), bbnSpfIgp(12), ospf(13), bgp(14) Sec.

IP Address Translation Table

IPNetToMediaTable = ARP Table other(1), invalid(2) invalid(2), dynamic(3), static(4) read-write

ICMP Group

ICMP Objects associated with ping icmpOutEchos - # ICMP echo messages sent icmpInEchoReps -# ICMP echo reply messages received Objects associated with traceroute/tracert icmpInTimeExcs # ICMP time exceeded messages received

TCP Group

TCP Connection Table

tcpConnState OBJECT-TYPE SYNTAX INTEGER { closed(1), listen(2), synSent(3), synReceived(4), established(5), finWait1(6), finWait2(7), closeWait(8), lastAck(9), closing(10), timeWait(11), deleteTCB(12) } ACCESS read-write STATUS mandatory … ::= { tcpConnEntry 1 } TCP Connection State

tcpConnTable

UDP Group

udpTable