Ik krijg gekke berichten als ik op de PDC (samba met FreeBSD 5.3) tcpdump draai
de volgende output:
21:15:21.133817 00:0d:60:83:d7:17 > 00:d0:b7:52:20:74, ethertype IPv4 (0x0800), length 54: IP (tos 0x10, ttl 64, id 48527, offset 0, flags [DF], length: 40) 192.168.0.1.22 > 81.57.115.6.13923: . [bad tcp cksum 7b03 (->78b0)!] 68656:68656(0) ack 3865 win 65535
21:15:21.481363 00:0b:ac:2f:20:15 > 01:80:c2:00:00:00, 802.3, length 60: LLC, dsap STP (0x42), ssap STP (0x42), cmd 0x03, 802.1d unknown version
21:15:21.804039 00:0d:60:83:d7:17 > 00:d0:b7:52:20:74, ethertype IPv4 (0x0800), length 1314: IP (tos 0x10, ttl 64, id 48528, offset 0, flags [DF], length: 1300) 192.168.0.1.22 > 81.57.115.6.13923: . 68656:69916(1260) ack 3865 win 65535
21:15:22.020460 00:d0:b7:52:20:74 > 00:0d:60:83:d7:17, ethertype IPv4 (0x0800), length 60: IP (tos 0x0, ttl 114, id 26168, offset 0, flags [DF], length: 40) 81.57.115.6.13923 > 192.168.0.1.22: . [tcp sum ok] 3865:3865(0) ack 69916 win 17640
21:15:22.020473 00:0d:60:83:d7:17 > 00:d0:b7:52:20:74, ethertype IPv4 (0x0800), length 190: IP (tos 0x10, ttl 64, id 48529, offset 0, flags [DF], length: 176) 192.168.0.1.22 > 81.57.115.6.13923: P 69916:70052(136) ack 3865 win 65535
21:15:22.042578 00:d0:b7:52:20:74 > 00:0d:60:83:d7:17, ethertype IPv4 (0x0800), length 106: IP (tos 0x0, ttl 114, id 26169, offset 0, flags [DF], length: 92) 81.57.115.6.13923 > 192.168.0.1.22: P 3865:3917(52) ack 70052 win 17504
21:15:22.133828 00:0d:60:83:d7:17 > 00:d0:b7:52:20:74, ethertype IPv4 (0x0800), length 54: IP (tos 0x10, ttl 64, id 48530, offset 0, flags [DF], length: 40) 192.168.0.1.22 > 81.57.115.6.13923: . [bad tcp cksum 7b03 (->7308)!] 70052:70052(0) ack 3917 win 65535
^C
292 packets captured
297 packets received by filter
0 packets dropped by kernel
Ik ben hierop gekomen daar er problemen zijn met personen die via een VPN (pptp) inloggen en gebruik maken van de pdc. Zij krijgen vaak timeouts etc. Wat ik niet begrijp dat er ook een bad tcp checksum gezien wordt.
Kan dit ook aan een switch liggen??
de volgende output:
21:15:21.133817 00:0d:60:83:d7:17 > 00:d0:b7:52:20:74, ethertype IPv4 (0x0800), length 54: IP (tos 0x10, ttl 64, id 48527, offset 0, flags [DF], length: 40) 192.168.0.1.22 > 81.57.115.6.13923: . [bad tcp cksum 7b03 (->78b0)!] 68656:68656(0) ack 3865 win 65535
21:15:21.481363 00:0b:ac:2f:20:15 > 01:80:c2:00:00:00, 802.3, length 60: LLC, dsap STP (0x42), ssap STP (0x42), cmd 0x03, 802.1d unknown version
21:15:21.804039 00:0d:60:83:d7:17 > 00:d0:b7:52:20:74, ethertype IPv4 (0x0800), length 1314: IP (tos 0x10, ttl 64, id 48528, offset 0, flags [DF], length: 1300) 192.168.0.1.22 > 81.57.115.6.13923: . 68656:69916(1260) ack 3865 win 65535
21:15:22.020460 00:d0:b7:52:20:74 > 00:0d:60:83:d7:17, ethertype IPv4 (0x0800), length 60: IP (tos 0x0, ttl 114, id 26168, offset 0, flags [DF], length: 40) 81.57.115.6.13923 > 192.168.0.1.22: . [tcp sum ok] 3865:3865(0) ack 69916 win 17640
21:15:22.020473 00:0d:60:83:d7:17 > 00:d0:b7:52:20:74, ethertype IPv4 (0x0800), length 190: IP (tos 0x10, ttl 64, id 48529, offset 0, flags [DF], length: 176) 192.168.0.1.22 > 81.57.115.6.13923: P 69916:70052(136) ack 3865 win 65535
21:15:22.042578 00:d0:b7:52:20:74 > 00:0d:60:83:d7:17, ethertype IPv4 (0x0800), length 106: IP (tos 0x0, ttl 114, id 26169, offset 0, flags [DF], length: 92) 81.57.115.6.13923 > 192.168.0.1.22: P 3865:3917(52) ack 70052 win 17504
21:15:22.133828 00:0d:60:83:d7:17 > 00:d0:b7:52:20:74, ethertype IPv4 (0x0800), length 54: IP (tos 0x10, ttl 64, id 48530, offset 0, flags [DF], length: 40) 192.168.0.1.22 > 81.57.115.6.13923: . [bad tcp cksum 7b03 (->7308)!] 70052:70052(0) ack 3917 win 65535
^C
292 packets captured
297 packets received by filter
0 packets dropped by kernel
Ik ben hierop gekomen daar er problemen zijn met personen die via een VPN (pptp) inloggen en gebruik maken van de pdc. Zij krijgen vaak timeouts etc. Wat ik niet begrijp dat er ook een bad tcp checksum gezien wordt.
Kan dit ook aan een switch liggen??