Load and performance analysis of IP router

System wide IP version specific traffic statistics

Per-interface IP statistics

Routing Principle

The routing of IP packet is the primary function of an IP router. An IP router consists of at least two network interfaces and enables the exchange of IP packets between IP hosts located on these two networks. Routing is required for hosts located in different IP networks that need to communicate.

The purpose of this document is to collect SNMP information available to assess the router load and possible malfunctions.

Note: a device originally not dedicated to this function can act as an IP router, it is the case of Linux, Windows for example.

Logical block a router with two interfaces:

routing process

As shown in the diagram above, the router determines the path from a routing table. The routing table is populated initially either manually (static routes) or dynamically by routing protocols such as RIP, OSPF.

Statistics on the routing performance of an IP router

Information natively provided by IP MIB objects

  • Number of routed IP packets
  • IP packets received and delivered to the higher protocol
  • IP packets discarded due to a lack of resources
  • IP packets ignored
  • rejected input packets
  • destroyed packages

calculated information

  • Percentage of IP packets delivered to the IP process relative to the total number of received packets
  • Percentage of IP packets ignored due to a lack of receive buffers
  • IP packet routed percentage relative to the total of received IP packets
  • Number of routing process calls

IP Statictics

The number of input datagrams forwarded by the system to their final destination

ipForwDatagrams

Or by using IP-MIB (RFC 4293) no IP version dependant

ipSystemStatsInForwDatagrams

The number of IP Datagrams discarded because no route could be found to transmit them to their destination

ipInDiscards

Or by using IP-MIB (RFC 4293) no IP version dependant

ipSystemStatsInDiscards

The number of IP Datagrams discarded due to lack of buffer resources

 

The number of input Datagrams discarded because the IP address in their IP header's destination field was not a valid address to be received.

The number of input Datagrams discarded due to errors in their IP headers particularly Time-To-Live counter expiration.

The number of locally-addressed IP Datagrams received successfully but discarded because of an unknown or unsupported protocol.

 

Percentage of IP Datagrams delivered to the IP Process to the total inbound Datagrams received.

ipInDelivers * 100 / ipInReceives

Or by using IP-MIB (RFC 4293) no IP version dependant

ipSystemStatsInDelivers.index * 100 / ipSystemStatsInReceives.index

Remark: These object are defined in SNMP table thus index value is required. Its index is formed from a single sub-id that represents the address type (IPv4 and IPv6) for which the statistics were counted.

Percentage of IP Datagrams discards due to no buffers.

ipInDiscards * 100 / ipInReceives

Or by using IP-MIB (RFC 4293) no IP version dependant

 ipSystemStatsInDiscards.index * 100 / ipSystemStatsInReceives.index

Remark: These object are defined in SNMP table thus index value is required. Its index is formed from a single sub-id that represents the address type (IPv4 and IPv6) for which the statistics were counted.

Percentage of IP Datagrams distant to Remote Address destinations to the total inbound Datagrams received.

ipForwDatagrams * 100 / ipInReceives

Or by using IP-MIB (RFC 4293) no IP version dependant

ipSystemStatsInForwDatagrams.index * 100 / ipSystemStatsInReceives.index

Percentage of IP Datagrams Discards to the IP Process to the total outbound Request Datagrams.

ipOutDiscards * 100 / ipOutRequests

Or by using IP-MIB (RFC 4293) no IP version dependant

ipSystemStatsOutDiscards.index * 100 / ipSystemStatsOutRequests.index

Remark: These object are defined in SNMP table thus index value is required. Its index is formed from a single sub-id that represents the address type (IPv4 and IPv6) for which the statistics were counted.

Number of Routing Process Invocations.

ipForwDatagrams + ipOutRequests

Or by using IP-MIB (RFC 4293) no IP version dependant

ipSystemStatsInForwDatagrams.index + ipSystemStatsOutRequests.index

Remark: These object are defined in SNMP table thus index value is required. Its index is formed from a single sub-id that represents the address type (IPv4 and IPv6) for which the statistics were counted.

 

IP traffic statistics from RFC 1213

These objects have been deprecated as a new IP version neutral table has been added in IP-MIB RFC4293)

Name Description
ipForwarding The indication of whether this entity is acting as an IP gateway in respect to the forwarding of datagrams received by, but not addressed to, this entity.  IP gateways forward datagrams.  IP hosts do not (except those source-routed via the host).
Note that for some managed nodes, this object may take on only a subset of the values possible.
Accordingly, it is appropriate for an agent to return a `badValue' response if a management station attempts to change this object to an inappropriate value.
ipDefaultTTL The default value inserted into the Time-To-Live field of the IP header of datagrams originated at this entity, whenever a TTL value is not supplied by the transport layer protocol.
ipInReceives The total number of input datagrams received from interfaces, including those received in error.
ipInHdrErrors The number of input datagrams discarded due to errors in their IP headers, including bad checksums, version number mismatch, other format errors, time-to-live exceeded, errors discovered in processing their IP options, etc.
ipInAddrErrors The number of input datagrams discarded because the IP address in their IP header's destination field was not a valid address to be received at this entity.  This count includes invalid addresses (e.g., 0.0.0.0) and addresses of unsupported Classes (e.g., Class E).  For entities which are not IP Gateways and therefore do not forward datagrams, this counter includes datagrams discarded because the destination address was not a local address.
ipForwDatagrams The number of input datagrams for which this entity was not their final IP destination, as a result of which an attempt was made to find a route to forward them to that final destination.
In entities which do not act as IP Gateways, this counter will include only those packets which were Source-Routed via this entity, and the Source- Route option processing was successful.
ipInUnknownProtos The number of locally-addressed datagrams received successfully but discarded because of an unknown or unsupported protocol.
ipInDiscards The number of input IP datagrams for which no problems were encountered to prevent their continued processing, but which were discarded (e.g., for lack of buffer space).  Note that this counter does not include any datagrams discarded while awaiting re-assembly.
ipInDelivers The total number of input datagrams successfully delivered to IP user-protocols (including ICMP).
ipOutRequests The total number of IP datagrams which local IP user-protocols (including ICMP) supplied to IP in requests for transmission.  Note that this counter does not include any datagrams counted in ipForwDatagrams.
ipOutDiscards The number of output IP datagrams for which no problem was encountered to prevent their transmission to their destination, but which were discarded (e.g., for lack of buffer space).  Note that this counter would include datagrams counted in ipForwDatagrams if any such packets met this (discretionary) discard criterion.
ipOutNoRoutes The number of IP datagrams discarded because no route could be found to transmit them to their destination.  Note that this counter includes any packets counted in ipForwDatagrams which meet this `no-route' criterion.  Note that this includes any
datagarms which a host cannot route because all of its default gateways are down.
ipReasmTimeout The maximum number of seconds which received fragments are held while they are awaiting reassembly at this entity.
ipReasmReqds The number of IP fragments received which needed to be reassembled at this entity.
ipReasmOKs The number of IP datagrams successfully re- assembled.
ipReasmFails The number of failures detected by the IP re- assembly algorithm (for whatever reason: timed out, errors, etc).  Note that this is not
necessarily a count of discarded IP fragments since some algorithms (notably the algorithm in RFC 815) can lose track of the number of fragments by combining them as they are received.
ipFragOKs The number of IP datagrams that have been successfully fragmented at this entity.
ipFragFails The number of IP datagrams that have been discarded because they needed to be fragmented at this entity but could not be, e.g., because their Don't Fragment flag was set.
ipFragCreates The number of IP datagram fragments that have been generated as a result of fragmentation at this entity.

 

 

System wide IP version specific traffic statistics ( ipSystemStatsTable from IP-MIB RFC4293)

The table containing system wide, IP version specific traffic statistics. This table and the ipIfStatsTable contain similar objects whose difference is in their
granularity. Where this table contains system wide traffic statistics, the ipIfStatsTable contains the same statistics but counted on a per-interface basis.

Its index is formed from a single sub-id that represents the address type(IPv4 and IPv6) for which the statistics were counted.

ipSystemStatsInReceives

The total number of input IP datagrams received, including those received in error.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsHCInReceives The total number of input IP datagrams received, including those received in error.  This object counts the same datagrams as ipSystemStatsInReceives, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsInOctets The total number of octets received in input IP datagrams, including those received in error.  Octets from datagrams counted in ipSystemStatsInReceives MUST be counted here.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsHCInOctets The total number of octets received in input IP datagrams, including those received in error.  This object counts the
same octets as ipSystemStatsInOctets, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsInHdrErrors The number of input IP datagrams discarded due to errors in their IP headers, including version number mismatch, other
format errors, hop count exceeded, errors discovered in processing their IP options, etc.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsInNoRoutes The number of input IP datagrams discarded because no route could be found to transmit them to their destination.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsInAddrErrors The number of input IP datagrams discarded because the IP address in their IP header's destination field was not a
valid address to be received at this entity.  This count includes invalid addresses (e.g., ::0).  For entities that are not IP routers and therefore do not forward datagrams, this counter includes datagrams discarded because the destination ddress was not a local address.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsInUnknownProtos The number of locally-addressed IP datagrams received successfully but discarded because of an unknown or unsupported protocol.
When tracking interface statistics, the counter of the interface to which these datagrams were addressed is incremented.  This interface might not be the same as the input interface for some of the datagrams.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsInTruncatedPkts The number of input IP datagrams discarded because the datagram frame didn't carry enough data.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsInForwDatagrams The number of input datagrams for which this entity was not their final IP destination and for which this entity attempted to find a route to forward them to that final destination.  In entities that do not act as IP routers,
this counter will include only those datagrams that were Source-Routed via this entity, and the Source-Route
processing was successful.
When tracking interface statistics, the counter of the incoming interface is incremented for each datagram.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsHCInForwDatagrams The number of input datagrams for which this entity was not their final IP destination and for which this entity attempted to find a route to forward them to that final destination.  This object counts the same packets as ipSystemStatsInForwDatagrams, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsReasmReqds The number of IP fragments received that needed to be reassembled at this interface.
When tracking interface statistics, the counter of the interface to which these fragments were addressed is incremented.  This interface might not be the same as the input interface for some of the fragments.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsReasmOKs The number of IP datagrams successfully reassembled.
When tracking interface statistics, the counter of the interface to which these datagrams were addressed is incremented.  This interface might not be the same as the input interface for some of the datagrams.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsReasmFails The number of failures detected by the IP re-assembly algorithm (for whatever reason: timed out, errors, etc.).
Note that this is not necessarily a count of discarded IP fragments since some algorithms (notably the algorithm in RFC 815) can lose track of the number of fragments by combining them as they are received.
When tracking interface statistics, the counter of the interface to which these fragments were addressed is incremented.  This interface might not be the same as the input interface for some of the fragments.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsInDiscards The number of input IP datagrams for which no problems were encountered to prevent their continued processing, but
were discarded (e.g., for lack of buffer space).  Note that this counter does not include any datagrams discarded while
awaiting re-assembly.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsInDelivers The total number of datagrams successfully delivered to IP user-protocols (including ICMP).
When tracking interface statistics, the counter of the interface to which these datagrams were addressed is incremented.  This interface might not be the same as the input interface for some of the datagrams.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsHCInDelivers The total number of datagrams successfully delivered to IP user-protocols (including ICMP).  This object counts the
same packets as ipSystemStatsInDelivers, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsOutRequests The total number of IP datagrams that local IP user- protocols (including ICMP) supplied to IP in requests for
transmission.  Note that this counter does not include any datagrams counted in ipSystemStatsOutForwDatagrams.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other
times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsHCOutRequests The total number of IP datagrams that local IP user- protocols (including ICMP) supplied to IP in requests for
transmission.  This object counts the same packets as ipSystemStatsOutRequests, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other
times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsOutNoRoutes

The number of locally generated IP datagrams discarded because no route could be found to transmit them to their
destination.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsOutForwDatagrams The number of datagrams for which this entity was not their final IP destination and for which it was successful in
finding a path to their final destination.  In entities that do not act as IP routers, this counter will include
only those datagrams that were Source-Routed via this entity, and the Source-Route processing was successful.
When tracking interface statistics, the counter of the outgoing interface is incremented for a successfully
forwarded datagram.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsHCOutForwDatagrams The number of datagrams for which this entity was not their final IP destination and for which it was successful in
finding a path to their final destination.  This object counts the same packets as ipSystemStatsOutForwDatagrams,
but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other
times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsOutDiscards The number of output IP datagrams for which no problem was encountered to prevent their transmission to their
destination, but were discarded (e.g., for lack of buffer space).  Note that this counter would include
datagrams counted in ipSystemStatsOutForwDatagrams if any such datagrams met this (discretionary) discard criterion.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other
times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsOutFragReqds The number of IP datagrams that would require fragmentation in order to be transmitted.
When tracking interface statistics, the counter of the outgoing interface is incremented for a successfully fragmented datagram.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsOutFragOKs The number of IP datagrams that have been successfully fragmented.
When tracking interface statistics, the counter of the outgoing interface is incremented for a successfully fragmented datagram.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsOutFragFails The number of IP datagrams that have been discarded because they needed to be fragmented but could not be.  This
includes IPv4 packets that have the DF bit set and IPv6 packets that are being forwarded and exceed the outgoing
link MTU. When tracking interface statistics, the counter of the outgoing interface is incremented for an unsuccessfully
fragmented datagram.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsOutFragCreates The number of output datagram fragments that have been generated as a result of IP fragmentation.
When tracking interface statistics, the counter of the outgoing interface is incremented for a successfully fragmented datagram.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsOutTransmits The total number of IP datagrams that this entity supplied to the lower layers for transmission.  This includes
datagrams generated locally and those forwarded by this entity.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsHCOutTransmits The total number of IP datagrams that this entity supplied to the lower layers for transmission.  This object counts
the same datagrams as ipSystemStatsOutTransmits, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other
times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsOutOctets The total number of octets in IP datagrams delivered to the lower layers for transmission.  Octets from datagrams
counted in ipSystemStatsOutTransmits MUST be counted here.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsHCOutOctets The total number of octets in IP datagrams delivered to the lower layers for transmission.  This objects counts the same
octets as ipSystemStatsOutOctets, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsInMcastPkts The number of IP multicast datagrams received.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsHCInMcastPkts The number of IP multicast datagrams received.  This object counts the same datagrams as ipSystemStatsInMcastPkts but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsInMcastOctets The total number of octets received in IP multicast datagrams.  Octets from datagrams counted in ipSystemStatsInMcastPkts MUST be counted here.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsHCInMcastOctets The total number of octets received in IP multicast datagrams.  This object counts the same octets as
ipSystemStatsInMcastOctets, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsOutMcastPkts The number of IP multicast datagrams transmitted.

Discontinuities in the value of this counter can occur at
re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsHCOutMcastPkts The number of IP multicast datagrams transmitted.  This object counts the same datagrams as ipSystemStatsOutMcastPkts, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsOutMcastOctets The total number of octets transmitted in IP multicast datagrams.  Octets from datagrams counted in ipSystemStatsOutMcastPkts MUST be counted here.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsHCOutMcastOctets The total number of octets transmitted in IP multicast datagrams.  This object counts the same octets as ipSystemStatsOutMcastOctets, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsInBcastPkts The number of IP broadcast datagrams received.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsHCInBcastPkts The number of IP broadcast datagrams received.  This object counts the same datagrams as ipSystemStatsInBcastPkts but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsOutBcastPkts The number of IP broadcast datagrams transmitted.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsHCOutBcastPkts The number of IP broadcast datagrams transmitted.  This object counts the same datagrams as
ipSystemStatsOutBcastPkts, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipSystemStatsDiscontinuityTime.

ipSystemStatsDiscontinuityTime The value of sysUpTime on the most recent occasion at which any one or more of this entry's counters suffered a
discontinuity.
If no such discontinuities have occurred since the last re- initialization of the local management subsystem, then this
object contains a zero value.
ipSystemStatsRefreshRate The minimum reasonable polling interval for this entry. This object provides an indication of the minimum amount of
time required to update the counters in this entry.

 

Per-interface IP statistics (ipIfStatsTable from IP-MIB RFC4293)

The table containing per-interface traffic statistics. This table and the ipSystemStatsTable contain similar objects whose difference is in their granularity. Where this table contains per-interface statistics, the ipSystemStatsTable contains the same statistics, but counted on a system wide basis.

Its index is formed from two sub-ids. The first represents the address type (IPv4 and IPv6), and the interface within that address type is represented by the second sub-id.

ipIfStatsInReceives The total number of input IP datagrams received, including those received in error.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsHCInReceives The total number of input IP datagrams received, including those received in error.  This object counts the same datagrams as ipIfStatsInReceives, but allows for larger
values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsInOctets The total number of octets received in input IP datagrams, including those received in error.  Octets from datagrams counted in ipIfStatsInReceives MUST be counted here.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsHCInOctets The total number of octets received in input IP datagrams, including those received in error.  This object counts the same octets as ipIfStatsInOctets, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsInHdrErrors

The number of input IP datagrams discarded due to errors in their IP headers, including version number mismatch, other format errors, hop count exceeded, errors discovered in
processing their IP options, etc.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsInNoRoutes The number of input IP datagrams discarded because no route could be found to transmit them to their destination. Discontinuities in the value of this counter can occur at
re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.
ipIfStatsInAddrErrors The number of input IP datagrams discarded because the IP address in their IP header's destination field was not a valid address to be received at this entity.  This count includes invalid addresses (e.g., ::0).  For entities that are not IP routers and therefore do not forward datagrams, this counter includes datagrams discarded because the destination address was not a local address.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsInUnknownProtos The number of locally-addressed IP datagrams received successfully but discarded because of an unknown or unsupported protocol. When tracking interface statistics, the counter of the interface to which these datagrams were addressed is incremented.  This interface might not be the same as the input interface for some of the datagrams.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsInTruncatedPkts The number of input IP datagrams discarded because the datagram frame didn't carry enough data.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsInForwDatagrams The number of input datagrams for which this entity was not their final IP destination and for which this entity attempted to find a route to forward them to that final destination.  In entities that do not act as IP routers, this counter will include only those datagrams that were Source-Routed via this entity, and the Source-Route processing was successful.
When tracking interface statistics, the counter of the incoming interface is incremented for each datagram.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsHCInForwDatagrams The number of input datagrams for which this entity was not their final IP destination and for which this entity attempted to find a route to forward them to that final destination.  This object counts the same packets as ipIfStatsInForwDatagrams, but allows for larger values. Discontinuities in the value of this counter can occur at
re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.
ipIfStatsReasmReqds The number of IP fragments received that needed to be reassembled at this interface. When tracking interface statistics, the counter of the interface to which these fragments were addressed is incremented.  This interface might not be the same as the input interface for some of the fragments.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsReasmOKs The number of IP datagrams successfully reassembled. When tracking interface statistics, the counter of the interface to which these datagrams were addressed is incremented.  This interface might not be the same as the input interface for some of the datagrams.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsReasmFails The number of failures detected by the IP re-assembly algorithm (for whatever reason: timed out, errors, etc.). Note that this is not necessarily a count of discarded IP
fragments since some algorithms (notably the algorithm in RFC 815) can lose track of the number of fragments by combining them as they are received. When tracking interface statistics, the counter of the interface to which these fragments were addressed is incremented.  This interface might not be the same as the input interface for some of the fragments.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsInDiscards The number of input IP datagrams for which no problems were encountered to prevent their continued processing, but were discarded (e.g., for lack of buffer space).  Note that
this counter does not include any datagrams discarded while awaiting re-assembly.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsInDelivers The total number of datagrams successfully delivered to IP user-protocols (including ICMP). When tracking interface statistics, the counter of the interface to which these datagrams were addressed is incremented.  This interface might not be the same as the input interface for some of the datagrams. Discontinuities in the value of this counter can occur at
re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.
ipIfStatsHCInDelivers The total number of datagrams successfully delivered to IP user-protocols (including ICMP).  This object counts the same packets as ipIfStatsInDelivers, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsOutRequests The total number of IP datagrams that local IP user- protocols (including ICMP) supplied to IP in requests for transmission.  Note that this counter does not include any datagrams ounted in ipIfStatsOutForwDatagrams.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsHCOutRequests The total number of IP datagrams that local IP user- protocols (including ICMP) supplied to IP in requests for transmission.  This object counts the same packets as ipIfStatsOutRequests, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsOutForwDatagrams The number of datagrams for which this entity was not their final IP destination and for which it was successful in finding a path to their final destination.  In entities that do not act as IP routers, this counter will include only those datagrams that were Source-Routed via this entity, and the Source-Route processing was successful. When tracking interface statistics, the counter of the outgoing interface is incremented for a successfully forwarded datagram.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsHCOutForwDatagrams

The number of datagrams for which this entity was not their final IP destination and for which it was successful in finding a path to their final destination.  This object counts the same packets as ipIfStatsOutForwDatagrams, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsOutDiscards The number of output IP datagrams for which no problem was encountered to prevent their transmission to their destination, but were discarded (e.g., for lack of buffer space).  Note that this counter would include datagrams counted in ipIfStatsOutForwDatagrams if any such datagrams met this (discretionary) discard criterion.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsOutFragReqds

The number of IP datagrams that would require fragmentation in order to be transmitted. When tracking interface statistics, the counter of the outgoing interface is incremented for a successfully fragmented datagram.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsOutFragOKs

The number of IP datagrams that have been successfully fragmented. When tracking interface statistics, the counter of the outgoing interface is incremented for a successfully
fragmented datagram.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsOutFragFails The number of IP datagrams that have been discarded because they needed to be fragmented but could not be.  This includes IPv4 packets that have the DF bit set and IPv6
packets that are being forwarded and exceed the outgoing link MTU. When tracking interface statistics, the counter of the outgoing interface is incremented for an unsuccessfully fragmented datagram.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsOutFragCreates The number of output datagram fragments that have been generated as a result of IP fragmentation. When tracking interface statistics, the counter of the outgoing interface is ncremented for a successfully fragmented datagram.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsOutTransmits The total number of IP datagrams that this entity supplied to the lower layers for transmission.  This includes datagrams generated locally and those forwarded by this entity.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsHCOutTransmits The total number of IP datagrams that this entity supplied to the lower layers for transmission.  This object counts the same datagrams as ipIfStatsOutTransmits, but allows for
larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsOutOctets The total number of octets in IP datagrams delivered to the lower layers for transmission.  Octets from datagrams counted in ipIfStatsOutTransmits MUST be counted here.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsHCOutOctets The total number of octets in IP datagrams delivered to the lower layers for transmission.  This objects counts the same octets as ipIfStatsOutOctets, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsInMcastPkts The number of IP multicast datagrams received.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsHCInMcastPkts

The number of IP multicast datagrams received.  This object counts the same datagrams as ipIfStatsInMcastPkts, but allows for larger values.

Discontinuities in the value of this ounter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsInMcastOctets The total number of octets received in IP multicast datagrams.  Octets from datagrams counted in ipIfStatsInMcastPkts MUST be counted here.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsHCInMcastOctets The total number of octets received in IP multicast datagrams.  This object counts the same octets as ipIfStatsInMcastOctets, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsOutMcastPkts The number of IP multicast datagrams transmitted.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsHCOutMcastPkts The number of IP multicast datagrams transmitted.  This object counts the same datagrams as ipIfStatsOutMcastPkts, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsOutMcastOctets The total number of octets transmitted in IP multicast datagrams.  Octets from datagrams counted in ipIfStatsOutMcastPkts MUST be counted here.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsHCOutMcastOctets The total number of octets transmitted in IP multicast datagrams.  This object counts the same octets as ipIfStatsOutMcastOctets, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsInBcastPkts The number of IP broadcast datagrams received.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsHCInBcastPkts The number of IP broadcast datagrams received.  This object counts the same datagrams as ipIfStatsInBcastPkts, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsOutBcastPkts The number of IP broadcast datagrams transmitted.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime.

ipIfStatsHCOutBcastPkts The number of IP broadcast datagrams transmitted.  This object counts the same datagrams as ipIfStatsOutBcastPkts, but allows for larger values.

Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ipIfStatsDiscontinuityTime">ipIfStatsDiscontinuityTime.

ipIfStatsDiscontinuityTime The value of sysUpTime on the most recent occasion at which any one or more of this entry's counters suffered a discontinuity. If no such discontinuities have occurred since the last re- initialization of the local management subsystem, then this object contains a zero value.
ipIfStatsRefreshRate The minimum reasonable polling interval for this entry. This object provides an indication of the minimum amount of time required to update the counters in this entry.