On Jul 29, 2008, at 10:43 PM, Darryl Dunkin wrote:
Hubs sure are fun...
This might be a stupid question, but where can one get small hubs these days? All of the common commodity (eg: 4 port Netgear) "hubs" these days are actually switches. What I am looking for is: Small enough to live in my notebook bag (e.g.: 4 port with a wall wart.) Cheap Simple 10/100/1000Mbps While a tap would work, I'd prefer a hub because I can then use it to connect machines together in a pinch. W --- In the past I have bought some cheap 4 port commodity switches (form Circuit City or somewhere similar), found the datasheet for the chipset (it was a Broadcom something or other) and tied the pin to ground that disables the learning mode (actually, I think that the pin just set the size of the learning table to be 0 entries). While this works, doing it once was more than enough :-)
I would trunk the ports you are monitoring, and run the port monitor on the trunk port instead (one trunk port, one port per VLAN, plus one span) which will help with your density. This is assuming the analysis software you have can read the dot1q tags, but means you do not need to burn two ports per monitor.
-----Original Message----- From: James Pleger [mailto:jpleger@gmail.com] Sent: Tuesday, July 29, 2008 19:26 To: nanog@merit.edu Subject: Re: Hardware capture platforms
There are several things that you can do with open source solutions, however looking at the data may be a bit more difficult than something like Network Generals or Solera Networks capture appliances. It is still doable and is definitely much much cheaper...
Something you might want to look into is traffic aggregation with a switch or hub. You can buy an Allied Telesyn switch and basically turn it into a hub by disabling switchport learning. Just an idea.
You can use regular old tcpdump with the -C option to rotate logs
tcpdump -i blah -s0 -C <filesize to rotate>, etc.
or you can use Daemonlogger which does pretty much the same thing...
http://www.snort.org/users/roesch/Site/Daemonlogger/Daemonlogger.html
Richard's blog @ http://taosecurity.blogspot.com/search?q=taps and especially his books (Tao of Network Security Monitoring and Extrusion Detection) are the best sources I have ever found, concerning [not only] taps and[/but] so much more on the subject - proper usage and best methodologies and practices for network monitoring (and not only for security!!!)
Stefan
On Tue, Jul 29, 2008 at 7:12 PM, Christopher Morrow <morrowc.lists@gmail.com
wrote:
On Wed, Jul 30, 2008 at 12:35 AM, Jared Mauch <jared@puck.nether.net> wrote:
Check out packet forensics depending on what your ultimate requirements are.
I would also add a 'see packet forensics'...
On Jul 29, 2008, at 7:10 PM, "John A. Kilpatrick" <john@hypergeek.net> wrote:
We've deployed a bunch taps in our network and now we need a
On Tue, Jul 29, 2008 at 6:45 PM, Network Fortius <netfortius@gmail.com> wrote: platform on
which to capture the data. Our bandwidth is currently pretty low but I've got 8 links to tap, which means I need 16 ports. Has anyone done any research on doing accurate packet capture with commodity hardware?
-- John A. Kilpatrick john@hypergeek.net Email| http://www.hypergeek.net/ john-page@hypergeek.net Text pages| ICQ: 19147504 remember: no obstacles/only challenges
-- "Build a man a fire, and he'll be warm for a day. Set a man on fire, and he'll be warm for the rest of his life." -- Terry Pratchett