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Old 03-24-2007, 02:43 AM   #1
infiniphunk
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Registered: Sep 2005
Location: Thunder Bay ON
Distribution: Slackware,Zenwalk,Ubuntu
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ssh troubleshooting hosts dyndns


Hello, I recently changed a server here at home from OpenBSD to zencore linux; normally I run pure-ftpd, sshd, httpd just to muck around, I'm in school learning to get my technician diploma. before when I had openbsd on it I had no problem ssh'ing to it from school, and from there to my main desktop and other server. after a power failure/electrical storm, my linksys router got fsckd and well, I had problems...lost 126 days uptime on it...after everything working nice...
Long story short, decided to try Zen-core 4.2 as a server for my main box, which I use mainly (only) for learning C++ for my class at school. I even gave my instructor at the college an acct on it so he could interact with me and maybe give me some direction in learning C in a gnu/linux / unix environment. Anyway, after the storm, I migrated the server over to Zenwalk and since then have been trying to get things back to normal. thus:

It's a PII running zenwalk core (previously openbsd) also acting as ftp server (with pure-ftpd) and open to the internet. on my inside network, I run a AMD k-6 with openBSD 4.0 as a file-server, using nfs to feed files thru a user acct to the zenwalk server.
The weirdest thing that I cannot figure out is, I can ssh to both servers from my LAN (ie: from my main desktop {ubuntu } but I cannot ssh to this box from school...or my parents house...or anywhere
Any ideas? I'm stumped...I've tried to troubleshoot this one, have read man-pages, googled around, and can't find any answers that help!
can YOU help me???


thanks,

Jerome
 
Old 03-24-2007, 04:24 AM   #2
acid_kewpie
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Registered: Jun 2001
Location: UK
Distribution: Gentoo, RHEL, Fedora, Centos
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well you've not said anythign about the topology of the network you are using. offhand i'd assume you're on a private LAN which isn't accessible from outside of it... if so you'd need to request port forwarding from an internet accessible device, which i'd assume is nevefr going to happen from the scenario you've described.
 
Old 03-24-2007, 02:27 PM   #3
infiniphunk
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Registered: Sep 2005
Location: Thunder Bay ON
Distribution: Slackware,Zenwalk,Ubuntu
Posts: 20

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I DO have port-forwarding enabled on the router for it; this has not changed. I've always been able to log in from all kinds of places, parents house, gf's house, school, etc etc, its just suddenly that I can no longer do so! I'm 100% positive I have port 22 and 21(for ftp, which does work). It's just ssh. I'm tempted to change /etc/ssh/sshd-conf to a port# other than 22 just to see if that's it. Any other ideas??
Thanks

Jer
 
Old 03-24-2007, 02:36 PM   #4
acid_kewpie
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on the ssh server run tcp dump and look for the incoming packets, e.g. "tcpdump -nv port 22" and try to connect... if you see any packets on the server, port forwarding is preaumbly ok, if not, it's not.
 
Old 03-25-2007, 03:54 PM   #5
infiniphunk
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Registered: Sep 2005
Location: Thunder Bay ON
Distribution: Slackware,Zenwalk,Ubuntu
Posts: 20

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Alright, what I really think happened here is that my linksys router got fried last week as a result of a power-failure/surge recently. Talking to a couple other locals in the last 48 hours has sorta confirmed that.
darn
 
  


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