[Nfdump-discuss] sFlow on Dell 62xx switches?

[Mark D. N. <mn...@wi...>]

Anyone have any luck collecting sFlow data from Dell PowerConnect
6248s?  We set it up and the data is not being handled correctly in
sfcapd -- constantly generates errors like this:

Jan 12 16:38:19 mindseye sfcapd[13661]: SFLOW: flow_sample_element length error (expected 94, found 96)
Jan 12 16:38:19 mindseye sfcapd[13661]: SFLOW: caught exception: 3


Any ideas?  I've used it fine before with HP Procurves, so I suspect
Dell is doing something wonky.  They are already broken in that they
won't generate flows for port channels (undocumented, but support folks
know it by heart).

I grabbed some packets with tshark, looks ok from the outer layer at
least (doesn't disect the samples themselves):

Internet Protocol, Src: 192.168.1.245 (192.168.1.245), Dst: 192.168.1.10
(192.168.1.10)
    Version: 4
    Header length: 20 bytes
    Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
        0000 00.. = Differentiated Services Codepoint: Default (0x00)
        .... ..0. = ECN-Capable Transport (ECT): 0
        .... ...0 = ECN-CE: 0
    Total Length: 638
    Identification: 0x3a0d (14861)
    Flags: 0x00
        0... = Reserved bit: Not set
        .0.. = Don't fragment: Not set
        ..0. = More fragments: Not set
    Fragment offset: 0
    Time to live: 64
    Protocol: UDP (0x11)
    Header checksum: 0xba12 [correct]
        [Good: True]
        [Bad : False]
    Source: 192.168.1.245 (192.168.1.245)
    Destination: 192.168.1.10 (192.168.1.10)
User Datagram Protocol, Src Port: sflow (6343), Dst Port: wizard (2001)
    Source port: sflow (6343)
    Destination port: wizard (2001)
    Length: 618
    Checksum: 0xce68
        [Good Checksum: False]
        [Bad Checksum: False]
InMon sFlow
    datagram version: 5
    agent address: 192.168.1.245 (192.168.1.245)
    Sub-agent ID: 0
    Sequence number: 2445309
    SysUptime: 687203338
    NumSamples: 4
    sFlow V5 samples (please write and contribute code to dissect them!)


Thanks,
Mark

-- 
Mark D. Nagel, CCIE #3177 <mn...@wi...>
Principal Consultant, Willing Minds LLC (http://www.willingminds.com)
cell: 949-279-5817, desk: 714-495-4001, fax: 714-646-8277

** For faster support response time, please
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