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Am Dienstag 12 Juni 2007 17:36 schrieb Hans-Werner Hilse: |
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> Hi, |
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> |
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> On Tue, 12 Jun 2007 17:17:04 +0200 Florian Philipp |
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> |
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> <f.philipp@××××××.de> wrote: |
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> > tcp 0 0 *:ftp *:* LISTEN |
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> |
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> That's it. Now better make sure that you were right when you stated |
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> your provider doesn't block it. BTW, if I as a provider had a no file |
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> sharing policy, I'd definitely block Port 21. Maybe I would leave Port |
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> 20 open (ftp-data), but on Port 21 only the ftp server is supposed to |
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> listen, not really the client. |
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> |
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> The other clients are supposed to use whatever port you specify, BTW. |
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> I'm using 50000-50400 myself, and others work fine, too. |
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> |
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> If you want to know whether incoming connections reach your site at all |
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> (not taking server software and firewall into account), run |
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> "tcpdump -vvns 1600 dst port 21" (I guess it wouldn't reveal anything |
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> at all). |
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> |
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> You're not by chance behind a router? |
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> |
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> -hwh |
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|
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dsl@HOMER_GENTOO64 ~ $ sudo tcpdump -vvns 1600 dst port 21 |
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Password: |
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tcpdump: listening on eth1, link-type EN10MB (Ethernet), capture size 1600 |
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bytes |
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18:37:12.543965 IP (tos 0x8, ttl 64, id 27970, offset 0, flags [DF], proto: |
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TCP (6), length: 60) 192.168.1.2.45269 > 89.57.3.60.21: S, cksum 0x8013 |
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(correct), 1866573467:1866573467(0) win 5840 <mss 1460,sackOK,timestamp |
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6212569 0,nop,wscale 5> |
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18:37:12.544426 IP (tos 0x8, ttl 64, id 17977, offset 0, flags [DF], proto: |
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TCP (6), length: 60) 192.168.1.2.45288 > 89.57.3.60.21: S, cksum 0x98ab |
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(correct), 1867615712:1867615712(0) win 5840 <mss 1460,sackOK,timestamp |
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6212569 0,nop,wscale 5> |
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19:07:52.537852 IP (tos 0x8, ttl 64, id 17709, offset 0, flags [DF], proto: |
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TCP (6), length: 60) 192.168.1.2.36423 > 89.57.3.60.21: S, cksum 0x3a4e |
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(correct), 3820262832:3820262832(0) win 5840 <mss 1460,sackOK,timestamp |
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6672541 0,nop,wscale 5> |
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[...] |
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27 packets captured |
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54 packets received by filter |
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0 packets dropped by kernel |
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|
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In the past Tiscali (my ISP) did not stop file sharing, they just slowed it |
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down to 10-12k. |
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|
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Yes, I am behind a router, NAT is activated, UPnP deactivated. That was no |
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problem up to now... |
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