You could start the ssh server on that machine with -vvv to get a detailled, verbose logging. That does not always lead to entries making clear what happens, but to entries you can use for googling (or asking here). I would also have a look at DNS - compare forward and reverse lookups (are they the same for the "from=..." entry?), does that Centos4-Box reach the DNS RELIABLY etc. SSH lies much emphasis on a working DNS. Dirk --On 11. August 2008 15:50:38 +1200 Clint Dilks <clintd at scms.waikato.ac.nz> wrote: > Hi People > > I am setting up some systems with ssh public keys and as part of this I > am using the from directive inside .ssh/authorized_keys. Currently I am > using the IP address to control the source. eg from="10.0.0.1" but on > one CentOS 4 System that is up to date this will only work if I replace > the IP with the DNS name of the server. I have verified that DNS is > resolving the DNS Name to the correct IP address on the server in > question and all seems to be fine. > Aside from this CentOS Box have only been able to test this out on some > old FC6 Machines > and they behave as I expected. Anyone got any ideas why this might be > happening ? I have compared the sshd config between the FC6 Machines and > the CentOS Box and can't spot anything that would explain the issue. > > Thanks for any ideas, and have a nice day :) > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos -------------------------------------------------------------- Dirk H. Schulz IT Systems Service Wiesenweg 12, 85567 Grafing Tel. 0 80 92/86 25 68 Fax. 0 80 92/86 25 72 -------------------------------------------------------------- Technik vom Feinsten - und das nötige Tuning