I often know and accept that portX on serverY is not the same as it was
10 minutes ago. Therefore I don't want to use ~/.ssh/known_hosts. So
I use "ssh -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null
-p portX serverY" but it is very lengthy to type and always yields this
message:
Warning: Permanently added '<host>,<ip>' (RSA) to the list of known hosts
where 'list of known hosts' presumably is /dev/null.
Is there a better way to suppress using host keys? I wish there was a
--no-hostkeys or similar option to do this.
If not, is there a way to avoid the above warning? It is misleading, and
I prefer not to train myself to avoid warnings.
(Yes, there are security problems when not using host keys. I know.)
I've tried to search the mailing list, but
http://marc.info/?l=secure-shell&w=2&r=1&s=stricthostkeychecking&q=b
shows some really weird results (try it!)
Further background
------------------
- We're on a LAN where our DHCP server is messed up. And corporate
wisdom dictates that it isn't worth it to ensure that hosts get the same
IP address at every reboot. We have to deal with it.
- We use port forwarding a lot, so port 2223 on serverX is forwarded to
a particular host right now, but a different one in 10 minutes. That is
reality for us.
- Also, we often test fresh installations, where each test involves
installation of the ssh package and hence the host keys differ from test
to test.
From a security standpoint an easy option to disable host keys when we
*know* they won't work is better than putting the
StrictHostKeyChecking=no and UserKnownHostsFile=/dev/null in
~/.ssh/config and then teaching the eye not to see the "Warning:
Permanently added..." message, isn't it?
Peter
--
Peter Valdemar Mørch
http://www.morch.com
--------
I often know and accept that portX on serverY is not the same as it was
10 minutes ago. Therefore I don't want to use ~/.ssh/known_hosts. So
I use "ssh -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null
-p portX serverY" but it is very lengthy to type and always yields this
message:
Warning: Permanently added '<host>,<ip>' (RSA) to the list of known hosts
where 'list of known hosts' presumably is /dev/null.
Is there a better way to suppress using host keys? I wish there was a
--no-hostkeys or similar option to do this.
If not, is there a way to avoid the above warning? It is misleading, and
I prefer not to train myself to avoid warnings.
(Yes, there are security problems when not using host keys. I know.)
I've tried to search the mailing list, but
http://marc.info/?l=secure-shell&w=2&r=1&s=stricthostkeychecking&q=b
shows some really weird results (try it!)
Further background
------------------
- We're on a LAN where our DHCP server is messed up. And corporate
wisdom dictates that it isn't worth it to ensure that hosts get the same
IP address at every reboot. We have to deal with it.
- We use port forwarding a lot, so port 2223 on serverX is forwarded to
a particular host right now, but a different one in 10 minutes. That is
reality for us.
- Also, we often test fresh installations, where each test involves
installation of the ssh package and hence the host keys differ from test
to test.
From a security standpoint an easy option to disable host keys when we
*know* they won't work is better than putting the
StrictHostKeyChecking=no and UserKnownHostsFile=/dev/null in
~/.ssh/config and then teaching the eye not to see the "Warning:
Permanently added..." message, isn't it?
Peter
--
Peter Valdemar Mørch
http://www.morch.com
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