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I have a problem that my server (CentOS 5) cannot connect I've used traceroute command like this:

traceroute -d -I

and I got the following lines:

traceroute to (, 30 hops max, 40 byte packets

1 ( 0.557 ms 0.883 ms 1.297 ms

2 ( 0.342 ms 1.299 ms 1.183 ms

3 ( 0.970 ms 1.117 ms 0.907 ms

4 ( 0.756 ms 1.065 ms 0.893 ms

5 tky001bf01.IIJ.Net ( 0.760 ms 0.761 ms 1.161 ms

6 ( 99.321 ms 99.473 ms 99.353 ms

7 sjc002bb10.IIJ.Net ( 114.983 ms 114.866 ms 114.834 ms

8 * * *

9 * * *

10 * * *

Each hosts (1~7) react to ping, but I can't check other hosts.

What should I do after traceroute?

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migrated from Sep 4 '11 at 9:24

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Can you ping directly? – Matteo Sep 4 '11 at 9:17
Yes. It didn't react to ping at my server(a). At Another server I have(b), react to ping. I think the network between (a) and twitter has some problems. – Mitsuaki Ishimoto Sep 4 '11 at 9:21

Your traceroute to the ruled out DNS and routing problems on your side. If you do not block twitter on the firewall, then the problems are outside your systems.

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I haven't blocked If problems are outside my system, shoud I set up my routing by using "route" command (or any other methods)? – Mitsuaki Ishimoto Sep 4 '11 at 16:08
I'm afraid you cannot solve the problem if it is not originating on your machine. Your routing is correct -- you only designate default gateway, and it seems to be the correct one, as you can see several different public IPs in the traceroute. If the problem persists, I'd contact the ISP. They may have some routing option open to them or will contact their routing peers. – Paweł Brodacki Sep 4 '11 at 17:10
Thanks for your advise!! I have asked! – Mitsuaki Ishimoto Sep 7 '11 at 0:12

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