Re: [CentOS] ssh_exchange_identification: Connection closed by remote host

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On Fri, 14 Sep 2012 17:09:46 +0200 (CEST), "M. Fioretti" mfioretti@nexaima.net said:

M> Yesterday I completed (fingers crossed) the switch to a different ADSL M> provider. From the moment I turned on the modem on the new ADSL line, I M> became unable to ssh into server A. All attempts abort with this M> message: M> ssh_exchange_identification: Connection closed by remote host

This is in the "grasping at straws" category, but have you tried connecting with a different cipher, like "blowfish" or "3des-cbc"?

If/as/when you get access to the server, can you disable TCP checksum offloading?

root# ethtool -K eth0 tx off rx off root# ethtool -t eth0 offline # adapter self-test