by Hello,
Since 1.5 years i care for a small network with a linux communication
server for all internet services (Suse 6.3, ISDN, squid, leafnode,
sendmail, No DNS, Autodial ). Until now everything was fine, but
suddenly after a normal http-request my ISDN4linux does not hang up
(during a whole night)
Here is the output of tcpdump -i ippp0
10:20:30.475195 as2-060.rp-plus.de.2052 > as1-038.rp-plus.de.1745: udp
255
10:20:30.475308 as1-038.rp-plus.de > as2-060.rp-plus.de: icmp:
as1-038.rp-plus.de udp port 1745 unreachable [tos 0xc0]
10:20:30.481871 as1-038.rp-plus.de.1326 > ns1.rp-plus.de.domain: 60451+
PTR? 38.236.221.149.in-addr.arpa. (45)
10:20:30.567431 ns1.rp-plus.de.domain > as1-038.rp-plus.de.1326: 60451*
1/2/2 PTR as1-038.rp-plus.de. (182) (DF)
10:20:30.570279 as1-038.rp-plus.de.1326 > ns1.rp-plus.de.domain: 60452+
PTR? 188.236.221.149.in-addr.arpa. (46)
10:20:30.623806 ns1.rp-plus.de.domain > as1-038.rp-plus.de.1326: 60452*
1/2/2 PTR as2-060.rp-plus.de. (183) (DF)
10:20:30.626616 as1-038.rp-plus.de.1326 > ns1.rp-plus.de.domain: 60453+
PTR? 30.247.221.149.in-addr.arpa. (45)
10:20:30.681930 ns1.rp-plus.de.domain > as1-038.rp-plus.de.1326: 60453*
1/2/2 PTR ns1.rp-plus.de. (178) (DF)
10:20:32.477123 as2-060.rp-plus.de.2052 > as1-038.rp-plus.de.1745: udp
255
10:20:32.477233 as1-038.rp-plus.de > as2-060.rp-plus.de: icmp:
as1-038.rp-plus.de udp port 1745 unreachable [tos 0xc0]
10:20:34.482445 as2-060.rp-plus.de.2052 > as1-038.rp-plus.de.1745: udp
255
10:20:34.482551 as1-038.rp-plus.de > as2-060.rp-plus.de: icmp:
as1-038.rp-plus.de udp port 1745 unreachable [tos 0xc0]
10:20:36.483128 as2-060.rp-plus.de.2052 > as1-038.rp-plus.de.1745: udp
255
10:20:36.483231 as1-038.rp-plus.de > as2-060.rp-plus.de: icmp:
as1-038.rp-plus.de udp port 1745 unreachable [tos 0xc0]
10:20:38.485187 as2-060.rp-plus.de.2052 > as1-038.rp-plus.de.1745: udp
255
10:20:38.485285 as1-038.rp-plus.de > as2-060.rp-plus.de: icmp:
as1-038.rp-plus.de udp port 1745 unreachable [tos 0xc0]
Hints:
-> rp-plus.de is the address of my provider
-> During the night there was no windows alive
My questions:
1.) tos stands for type of service, but what does this mean? what is
service type c0?
2.) I don't understand the output: which host has initiated this
udp-port connection, resp. hold alive? What is the direction of the
packets?
3.) I don't found neither Port 255 nor 1745 in /etc/services.
.. and
4.) What has happened?
Thanks a lot,
Michael Senge