Allegedly, on or about 19 November 2013, Beartooth sent: > > I have several machines on a LAN (and a KVM switch that I use > when they're all functioning). Most are online over ethernet via a > Linksys modem running DD-WRT v24-sp2 (10/10/09)micro; and I can > normally ssh from any to any. > > But at present there are two on which ssh in either direction > gets only Connection refused. Both are running F18, fully updated. > > What is likely to be the glitch, and how can I fix it? Reboot the things in the middle (the Linksys modem & KVM switch) that'd be my first step. Perhaps shutdown, pull out the power, and restart completely fresh. Swap some network cables around between different sockets. Check that ssh daemon is running, firewalls have suitable holes in them, and SELinux allows sshd. In operation, if you see network indicator lights madly flicking on and off, for no apparent reason, that can be a network "flapping." Or, if you see a light that's permanently on, even when it shouldn't be (e.g. it should flicker when there's traffic, go out when equipment is off). They could be temporary glitches that'll be fixed by a hard reset, it could be permanent component failure. I've had to replace several network switches, over the years, as they've crapped out for one reason or another. There's been simple power supply pack failures. And they span between buildings, with a fairly long UTP cable, so I suspect EMR picked up from lightning storms may zap some of the circuitry. And since no affordable network devices bother to put isolating transformers on inputs and outputs (galvanic isolation), any grounding differences between buildings are probably stressing input circuits. Though one managed to survive a rather bad mains active to earth leak, for a very long time (wildlife in the ceiling attacking the lighting wiring - on a couple of occasions I've heard rustles in the ceiling, brief lighting dims and a nasty electric-chair buzzing sounds, animal screeching then running like mad through the roof, which has been somewhat amusing to hear the buggers get their comeuppance). And I've still got the copper wiring spot-welded to the screwdriver that I experimentally placed between two lots of earth wiring. I'm glad I mistrusted someone else's electrical work enough to test it, rather than put my fingers on earth wiring expecting it to be safe. I wasn't expecting that rather extreme reaction, though. That's my situation (sporadic hardware failures), but it may shed light on someone else having equipment failures. -- [tim@localhost ~]$ uname -rsvp Linux 3.8.13-100.fc17.x86_64 #1 SMP Mon May 13 13:36:17 UTC 2013 x86_64 All mail to my mailbox is automatically deleted, there is no point trying to privately email me, I will only read messages posted to the public lists. George Orwell's '1984' was supposed to be a warning against tyranny, not a set of instructions for supposedly democratic governments. -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
