Thread: Cannot ssh to *one* server from *one* location; everything else works

i remotely administer friend's server. has dynamic ip address, use freedns.afraid.org give domain name. server running apache server, ftp server, , ssh server remote administration. of these services running fine.

1 day 3 months ago, tried ssh server work around 10:30, , got error message. assumed server had crashed, since had sshed fine work server around 8:00 morning. had friend restart server, still wasn't working. of efforts track down problem have been in vain. since day, when attempt ssh server work, get:

code:

ssh_exchange_identification: connection closed remote host

after pause of 5 8 seconds. error when ssh this server from work--not when connect server anywhere else, nor when connect ssh server form work, nor when connect http or ftp work. i'm mystified, can't find special particular setup cause break. i'm using laptop, it's not because it's different computer. director of technology assures me hasn't twiddled firewall (although else might have, it's not particularly likely.) if helps any, have sshguard installed on server, although documentation says if sshguard causing problem, have gone away now.

if has ideas, i'd grateful. using remote server testing work, , not having available has introduced complexity i'd prefer not have deal with.

Forum The Ubuntu Forum Community Ubuntu Official Flavours Support Networking & Wireless [all variants] Cannot ssh to *one* server from *one* location; everything else works

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