June 2010
Intermediate to advanced
224 pages
5h 18m
English
Content preview from Network Flow AnalysisBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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Analyzing Individual Flows from Reports
Look back at the ip-source-address report from in Using Variables: SORT in Using Variables: Report Type. Notice how the host 207.46.209.247 used the most bandwidth, 131,391,013 octets. That's 131,391,013 divided by 1,024, which is about 128,312KB, or 125MB. The obvious question is "What did that host send in all those octets with but so few flows?"
To find out, use flow-nfilter to answer that question. Because this is a one-off query that probably won't be repeated, just configure the filter on the command line.
# flow-cat * | flow-nfilter -F ip-src-addr -v ADDR=207.46.209.247 | flow-print srcIP dstIP prot srcPort dstPort octets packets 207.46.209.247 192.0.2.4 ❶ 6 ❷ 80 51538 16499752 11018 207.46.209.247 ...Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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