Getting ssd started at boot ...

[jc at trillian.mit.edu (John Chambers)]

After a couple of recent power failures,  I've  found  that  sshd  is
running  but  it  always  rejects logins with the message "Permission
denied, please try again." The first several times, I fixed  this  by
killing  sshd  and restarting it by hand, which seems to have worked.
But this time, it doesn't.  When I start sshd, what it says is:

: /usr/local/sbin/sshd  &
[1] 5814
Disabling protocol version 2. Could not load host key
[1]    Done                          /usr/local/sbin/sshd
:

I'm not sure what it's complaining about here.  It's running as root,
and  is  also  setuid-root  (just  to  make sure).  I noticed that it
doesn't give me a clue as to what file it's trying to read  the  host
key  from  so  I  used the -h option to tell it to read from the file
/usr/local/etc/ssh_host_key, the default, and this has no  effect  on
anything.

Anyhow, when I try to ssh in from another machine, I get:

: ssh jc.tzo.net
jc at jc.tzo.net's password:
Permission denied, please try again.
jc at jc.tzo.net's password:

This repeats 3 times and then gives up.  Note that it isn't  actually
saying  that the password is bad; it'd saying that some (unspecified)
permission has been denied.  But it gives no clue as to what  it  was
checking  permissions  on.   I  can verify that jc.tzo.net is my home
machine by looking at /var/log/messages, which shows things like:

Jan 28 16:41:17 kendy sshd[6011]: Connection from 18.62.1.54 port 1345
Jan 28 16:41:17 kendy sshd[6011]: Failed rsa for jc from 18.62.1.54 port 1345
Jan 28 16:41:20 kendy sshd[6011]: Failed password for jc from 18.62.1.54 port 1345

This verifies that ssh is connecting to sshd on my  machine,  and  it
does seem to be saying that the password is the problem. There's also
a "Failed rsa" message, but I don't seem to find anything in TFM that
explains what this signifies.

Checking with "su - jc" verifies that I'm typing the right  password.
Looking  in  my  .ssh  directory shows that known_hosts seems to have
changed a few minutes ago, and random_seed changed 3  days  ago,  but
I'm  not sure whether these are significant.  TFM doesn't seem to say
quite what this might signify.

So I've run out of clues. Any idea how to learn why sshd is rejecting
all my passwords, and make it start working again?