Net::sFlow - decode sFlow datagrams
use Net::sFlow;
use IO::Socket::INET;
my $sock = IO::Socket::INET->new( LocalPort => '6343',
Proto => 'udp')
or die "Can't bind : $@\n";
while ($sock->recv($packet,1548)) {
&processPacket($packet);
}
die "Socket recv: $!";
sub processPacket {
my $sFlowPacket = shift;
# now we actually call the Net::sFlow::decode() function
my ($sFlowDatagramRef, $sFlowSamplesRef, $errorsRef) = Net::sFlow::decode($sFlowPacket);
# print errors
foreach my $error (@{$errorsRef}) {
warn "$error";
}
# print sflow data
print "===Datagram===\n";
print "sFlow version: $sFlowDatagramRef->{sFlowVersion}\n";
print "datagram sequence number: $sFlowDatagramRef->{datagramSequenceNumber}\n";
foreach my $sFlowSample (@{$sFlowSamplesRef}) {
print "\n";
print "---Sample---\n";
print "sample sequence number: $sFlowSample->{sampleSequenceNumber}\n";
}
}
The sFlow module provides a mechanism to parse and decode sFlow datagrams. It supports sFlow version 2/4 (RFC 3176 - http://www.ietf.org/rfc/rfc3176.txt) and sFlow version 5 (Memo - http://sflow.org/sflow\_version\_5.txt).
The module's functionality is provided by a single (exportable) function, decode().
For more examples have a look into the 'examples' directory.
($datagram, $samples, $error) = Net::sFlow::decode($udp_data);
Returns a HASH reference containing the datagram data, an ARRAY reference with the sample data (each array element contains a HASH reference for one sample) and in case of an error a reference to an ARRAY containing the error messages.
-
$datagram
A HASH reference containing information about the sFlow datagram, with the following keys:
sFlowVersion AgentIpVersion AgentIp datagramSequenceNumber agentUptime samplesInPacketIn the case of sFlow v5, there is an additional key:
subAgentId -
$samples
Reference to a list of HASH references, each one representing one sample. Depending on the sFlow version and type of hardware where the data comes from (router, switch, etc.), the hash contains the following additional keys:
In case of sFlow <= 4:
sampleType sampleSequenceNumber sourceIdType sourceIdIndexIf it's a sFlow <= 4 flowsample you will get the following additional keys:
samplingRate samplePool drops inputInterface outputInterface packetDataType extendedDataInSampleIf it's a sFlow <= 4 countersample you will get these additional keys:
counterSamplingInterval countersVersionIn case of sFlow >= 5 you will first get enterprise, format and length information:
sampleTypeEnterprise sampleTypeFormat sampleLengthIf the sample is a Foundry ACL based sample (enterprise == 1991 and format == 1) you will receive the following information:
FoundryFlags FoundryGroupIDIn case of a flowsample (enterprise == 0 and format == 1):
sampleSequenceNumber sourceIdType sourceIdIndex samplingRate samplePool drops inputInterface outputInterface flowRecordsCountIf it's an expanded flowsample (enterprise == 0 and format == 3) you will get these additional keys instead of inputInterface and outputInterface:
inputInterfaceFormat inputInterfaceValue outputInterfaceFormat outputInterfaceValueIn case of a countersample (enterprise == 0 and format == 2) or an expanded countersample (enterprise == 0 and format == 4):
sampleSequenceNumber sourceIdType sourceIdIndex counterRecordsCount counterDataLengthDepending on the hardware you can get the following additional keys:
Header data (sFlow format):
HEADERDATA HeaderProtocol HeaderFrameLength HeaderStrippedLength HeaderSizeByte HeaderSizeBit HeaderBinAdditional Header data decoded from the raw packet header:
HeaderEtherSrcMac HeaderEtherDestMac HeaderType (ether type) HeaderDatalen (of the whole packet including ethernet header)Ethernet frame data:
ETHERNETFRAMEDATA EtherMacPacketlength EtherSrcMac EtherDestMac EtherPackettypeIPv4 data:
IPv4DATA IPv4Packetlength IPv4NextHeaderProtocol IPv4srcIp IPv4destIp IPv4srcPort IPv4destPort IPv4tcpFlags IPv4tosIPv6 data:
IPv6DATA IPv6Packetlength IPv6NextHeaderProto IPv6srcIp IPv6destIp IPv6srcPort IPv6destPort IPv6tcpFlags IPv6PrioritySwitch data:
SWITCHDATA SwitchSrcVlan SwitchSrcPriority SwitchDestVlan SwitchDestPriorityRouter data:
ROUTERDATA RouterIpVersionNextHopRouter RouterIpAddressNextHopRouter RouterSrcMask RouterDestMaskGateway data:
GATEWAYDATA GatewayIpVersionNextHopRouter (only in case of sFlow v5) GatewayIpAddressNextHopRouter (only in case of sFlow v5) GatewayAsRouter GatewayAsSource GatewayAsSourcePeer GatewayDestAsPathsCount GatewayDestAsPaths (arrayreference) each enty contains a hashreference: asPathSegmentType lengthAsList AsPath (arrayreference, asNumbers as entries) GatewayLengthCommunitiesList (added in sFlow v4) GatewayCommunities (arrayreference, added in sFlow v4) each enty contains a community (added in sFlow v4) localPrefUser data:
USERDATA UserSrcCharset (only in case of sFlow v5) UserLengthSrcString UserSrcString UserDestCharset (only in case of sFlow v5) UserLengthDestString UserDestStringUrl data (added in sFlow v3):
URLDATA UrlDirection UrlLength Url UrlHostLength (only in case of sFlow v5) UrlHost (only in case of sFlow v5)The following keys can be only available in sFlow v5:
Mpls data:
MPLSDATA MplsIpVersionNextHopRouter MplsIpAddressNextHopRouter MplsInLabelStackCount MplsInLabelStack (arrayreference containing MplsInLabels) MplsOutLabelStackCount MplsOutLabelStack (arrayreference containing MplsOutLabels)Nat data:
NATDATA NatIpVersionSrcAddress NatSrcAddress NatIpVersionDestAddress NatDestAddressMpls tunnel:
MPLSTUNNEL MplsTunnelNameLength MplsTunnelName MplsTunnelId MplsTunnelCosValueMpls vc:
MPLSVC MplsVcInstanceNameLength MplsVcInstanceName MplsVcId MplsVcLabelCosValueMpls fec:
MPLSFEC MplsFtnDescrLength MplsFtnDescr MplsFtnMaskMpls lpv fec:
MPLSLPVFEC MplsFecAddrPrefixLengthVlan tunnel:
VLANTUNNEL VlanTunnelLayerStackCount VlanTunnelLayerStack (arrayreference containing VlanTunnelLayer entries)The following keys are also available in sFlow < 5:
Counter generic:
COUNTERGENERIC ifIndex ifType ifSpeed ifDirection ifAdminStatus ifOperStatus ifInOctets ifInUcastPkts ifInMulticastPkts ifInBroadcastPkts ifInDiscards ifInErrors ifInUnknownProtos ifOutOctets ifOutUcastPkts ifOutMulticastPkts ifOutBroadcastPkts ifOutDiscards ifOutErrors ifPromiscuousModeCounter ethernet:
COUNTERETHERNET dot3StatsAlignmentErrors dot3StatsFCSErrors dot3StatsSingleCollisionFrames dot3StatsMultipleCollisionFrames dot3StatsSQETestErrors dot3StatsDeferredTransmissions dot3StatsLateCollisions dot3StatsExcessiveCollisions dot3StatsInternalMacTransmitErrors dot3StatsCarrierSenseErrors dot3StatsFrameTooLongs dot3StatsInternalMacReceiveErrors dot3StatsSymbolErrorsCounter tokenring:
COUNTERTOKENRING dot5StatsLineErrors dot5StatsBurstErrors dot5StatsACErrors dot5StatsAbortTransErrors dot5StatsInternalErrors dot5StatsLostFrameErrors dot5StatsReceiveCongestions dot5StatsFrameCopiedErrors dot5StatsTokenErrors dot5StatsSoftErrors dot5StatsHardErrors dot5StatsSignalLoss dot5StatsTransmitBeacons dot5StatsRecoverys dot5StatsLobeWires dot5StatsRemoves dot5StatsSingles dot5StatsFreqErrorsCounter vg:
COUNTERVG dot12InHighPriorityFrames dot12InHighPriorityOctets dot12InNormPriorityFrames dot12InNormPriorityOctets dot12InIPMErrors dot12InOversizeFrameErrors dot12InDataErrors dot12InNullAddressedFrames dot12OutHighPriorityFrames dot12OutHighPriorityOctets dot12TransitionIntoTrainings dot12HCInHighPriorityOctets dot12HCInNormPriorityOctets dot12HCOutHighPriorityOctetsCounter vlan:
COUNTERVLAN vlan_id octets ucastPkts multicastPkts broadcastPkts discardsCounter lag:
COUNTERLAG dot3adAggPortActorSystemID dot3adAggPortPartnerOperSystemID dot3adAggPortAttachedAggID dot3adAggPortActorAdminState dot3adAggPortActorOperState dot3adAggPortPartnerAdminState dot3adAggPortPartnerOperState dot3adAggPortStatsLACPDUsRx dot3adAggPortStatsMarkerPDUsRx dot3adAggPortStatsMarkerResponsePDUsRx dot3adAggPortStatsUnknownRx dot3adAggPortStatsIllegalRx dot3adAggPortStatsLACPDUsTx dot3adAggPortStatsMarkerPDUsTx dot3adAggPortStatsMarkerResponsePDUsTxCounter processor (only in sFlow v5):
COUNTERPROCESSOR cpu5s cpu1m cpu5m memoryTotal memoryFreeCounter HTTP:
COUNTERHTTP methodOptionCount methodGetCount methodHeadCount methodPostCount methodPutCount methodDeleteCount methodTraceCount methodConnectCount methodOtherCount status1xxCount status2xxCount status3xxCount status4xxCount status5xxCount statusOtherCount -
$error
Reference to a list of error messages.
The decode() function will blindly attempt to decode the data you provide. There are some tests for the appropriate values at various places (where it is feasible to test - like enterprises, formats, versionnumbers, etc.), but in general the GIGO principle still stands: Garbage In / Garbage Out.
sFlow v4 http://www.ietf.org/rfc/rfc3176.txt
sFlow v5 http://sflow.org/sflow\_version\_5.txt
Math::BigInt
Elisa Jasinska elisa@bigwaveit.org
Please send comments or bug reports to elisa@bigwaveit.org and/or sflow@ams-ix.net
Copyright (c) 2006 - 2015 AMS-IX B.V.
This package is free software and is provided "as is" without express or implied warranty. It may be used, redistributed and/or modified under the terms of the Perl Artistic License (see http://www.perl.com/perl/misc/Artistic.html)
