Predefined CLEAR-Flow Counters

A number of packet statistics are gathered by the ExtremeXOS kernel.

To allow you to use these statistics in CLEAR-Flow expressions, these kernel counters are now available for use with CLEAR-Flow. Most of the counter names are based directly on well known names from common kernel structures and MIBs. The names are modified from their familiar form by pre-pending the characters sys_ to the counter names.

Table 1. Predefined CLEAR-Flow Counters
Counter Name Description
sys_IpInReceives The total number of input IP packets received from interfaces, including those received in error.
sys_IpInHdrErrors The number of input IP packets 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.
sys_IpInAddrErrors The number of input IP packets 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 (for example, 0.0.0.0) and addresses of unsupported Classes (for example, Class E).
sys_IpForwDatagrams The number of input IP packets 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.
sys_IpInUnknownProtos The number of locally-addressed IP packets received successfully but discarded because of an unknown or unsupported protocol.
sys_IpInDiscards The number of input IP packets for which no problems were encountered to prevent their continued processing, but which were discarded (for example, for lack of buffer space). Note that this counter does not include any IP packets discarded while awaiting re-assembly.
sys_IpInDelivers The total number of input IP packets successfully delivered to IP user-protocols (including ICMP).
sys_IpOutRequests The total number of IP packets which local IP user-protocols (including ICMP) supplied to IP in requests for transmission. Note that this counter does not include any IP packets counted in ipForwDatagrams.
sys_IpOutDiscards The number of output IP packets for which no problem was encountered to prevent their transmission to their destination, but which were discarded (for example, for lack of buffer space). Note that this counter would include IP packets counted in ipForwDatagrams if any such packets met this (discretionary) discard criterion.
sys_IpOutNoRoutes The number of IP packets 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.
sys_IpReasmTimeout The maximum number of seconds which received fragments are held while they are awaiting reassembly at this entity.
sys_IpReasmReqds The number of IP fragments received which needed to be reassembled at this entity.
sys_IpReasmOKs The number of IP packets successfully re-assembled.
sys_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.
sys_IpFragOKs The number of IP packets that have been successfully fragmented at this entity.
sys_IpFragFails The number of IP packets that have been discarded because they needed to be fragmented at this entity but could not be, for example, because their Don't Fragment flag was set.
sys_IpFragCreates The number of IP packet fragments that have been generated as a result of fragmentation at this entity.
sys_IcmpInMsgs The total number of ICMP messages which the entity received. Note that this counter includes all those counted by icmpInErrors.
sys_IcmpInErrors The number of ICMP messages which the entity received but determined as having ICMP-specific errors (bad ICMP checksums, bad length, etc.).
sys_IcmpInDestUnreachs The number of ICMP Destination Unreachable messages received.
sys_IcmpInTimeExcds The number of ICMP Time Exceeded messages received.
sys_IcmpInParmProbs The number of ICMP Parameter Problem messages received.
sys_IcmpInSrcQuenchs The number of ICMP Source Quench messages received.
sys_IcmpInRedirects The number of ICMP Redirect messages received.
sys_IcmpInEchos The number of ICMP Echo (request) messages received.
sys_IcmpInEchoReps The number of ICMP Echo Reply messages received.
sys_IcmpInTimestamps The number of ICMP Timestamp (request) messages received.
sys_IcmpInTimestampReps The number of ICMP Timestamp Reply messages received.
sys_IcmpInAddrMasks The number of ICMP Address Mask Request messages received.
sys_IcmpInAddrMaskReps The number of ICMP Address Mask Reply messages received.
sys_IcmpOutMsgs The total number of ICMP messages which this entity attempted to send. Note that this counter includes all those counted by IcmpOutErrors.
sys_IcmpOutErrors The number of ICMP messages which this entity did not send due to problems discovered within ICMP such as a lack of buffers. This value should not include errors discovered outside the ICMP layer such as the inability of IP to route the resultant datagram. In some implementations there may be no types of error which contribute to this counter's value.
sys_IcmpOutDestUnreachs The number of ICMP Destination Unreachable messages sent.
sys_IcmpOutTimeExcds The number of ICMP Time Exceeded messages sent.
sys_IcmpOutParmProbs The number of ICMP Parameter Problem messages sent.
sys_IcmpOutSrcQuenchs The number of ICMP Source Quench messages sent.
sys_IcmpOutRedirects The number of ICMP Redirect messages sent.
sys_IcmpOutEchos The number of ICMP Echo (request) messages sent.
sys_IcmpOutEchoReps The number of ICMP Echo Reply messages sent.
sys_IcmpOutTimestamps The number of ICMP Timestamp (request) messages sent.
sys_IcmpOutTimestampReps The number of ICMP Timestamp Reply messages sent.
sys_IcmpOutAddrMasks The number of ICMP Address Mask Request messages sent.
sys_IcmpOutAddrMaskReps The number of ICMP Address Mask Reply messages sent.
sys_IcmpInProtoUnreachs The number of incoming ICMP packets addressed to a not-in-use / unreachable / invalid protocol. This message is in the general category of ICMP destination unreachable error messages.
sys_IcmpInBadLen The number of incoming bad ICMP length packets.
sys_IcmpInBadCode The number of incoming ICMP packets with a bad code field value.
sys_IcmpInTooShort The number of incoming short ICMP packets.
sys_IcmpInBadChksum The number of incoming ICMP packets with bad checksums.
sys_IcmpInRouterAdv The number of incoming ICMP router advertisements. Router advertisements are used by IP hosts to discover addresses of neighboring routers.
sys_IcmpOutProtoUnreachs The number of outgoing ICMP packets addressed to a not-in-use / unreachable / invalid protocol. This message is in the general category of ICMP destination unreachable error messages.
sys_IcmpOutRouterAdv The number of outgoing ICMP router advertisements. Router advertisements are used by IP hosts to discover addresses of neighboring routers.
sys_IgmpInQueries The number of Host Membership Query messages that have been received on this interface.
sys_IgmpInReports The number of Host Membership Report messages that have been received on this interface for this group address.
sys_IgmpInLeaves The number of incoming IGMP leave requests.
sys_IgmpInErrors The number of incoming IGMP errors.
sys_IgmpOutQueries The number of Host Membership Query messages that have been sent on this interface.
sys_IgmpOutReports The number of Host Membership Report messages that have been sent on this interface for this group address.
sys_IgmpOutLeaves The number of outgoing IGMP leave requests.

1 Most of these descriptions can be found in RFC 2011, SNMPv2 Management Information Base for the Internet Protocol using SMIv2.
2 The length of an ICMP packet depends on the type and code field.