I am trying to connect to a network device using ssh.
I get the following result:-
Unable to negotiate with 192.168.169.132 port 22: no matching host key type found. Their offer: ssh-rsa
I have spent a long time on Google trying to find solution but still not getting a connection.
Please can somebody help.
Is this your Server?
192.168.169.132
Change on the Server:
PasswordAuthentication no
to
PasswordAuthentication yes
in /etc/ssh/sshd_config
Restart the ssh-Server.
ssh -o "HostKeyAlgorithms ssh-rsa" user@hostname
How is host key related to authentication? Authentication happens after connection to host is established.
Many thanks. A couple of questions:
The IP address is the fixed address of the remote (client?) network device.
My laptop is on another dhcp address on same subnet.
I have no sshd_config file, only two directories ssh_config.d and sshd_config.d
I assume I create a sshd_config file but am not sure about syntax and context. Should I just create the sshd_config file and have one line **PasswordAuthentication yes?
**
I have tried the suggested fix and now I get a different error:-
Unable to negotiate with 192.168.169.132 port 22: no matching cipher found. Their offer: aes256-cbc,3des-cbc
What is missing here. Is it a problem with out of date firmware on the network device or some setting on my laptop?
Hi
So you need to be more clear in describing the issue 
The target system is 192.168.169.132, your on a host at the same ip address 192.168.169.xxx?
Say you want to setup root user access;
ssh-copy-id root@192.168.169.132
If just your user to the same user on 192.168.169.132 then just copy-id to the ip address.
No local configuration required…
Hi
The cipher option…
ssh -Q cipher
ssh -c aes256-cbc user@host
ssh -c 3des-cbc user@host
I shall explain in more detail.
I have an APC UPS which has a Network Management Card (NMC) on which I was trying to update the firmware. This was supposed to be done using an APC Windoze app and I implemented this using a copper connection from NIC configured on the same subnet.
Unfortunately the update crashed before completion and left me with a broken system which I was not able to revive but which I could still access because the IP remained working and I was able to access using ftp. Looking round all the accessible directories on the device it seems that there could be quite a lot missing including the config.ini file.
My plan is therefore to copy the config.ini from another NMC borrowed from a working system. There are instructions for doing this in the APC manuals but I need to access both devices using ftp.
I had been trying to access the working device first using ssh because I am working across network with wifi and managed switches in between and was not sure about ftp. This is where I have reached.
The ssh exercise was me being side tracked as I really should be using ftp but I do need to follow the APC instructions for getting the good config.ini from my working device and all attempts get me connection refused thus:-
alastair@localhost:~> ftp 192.168.169.132
ftp: Can't connect to `192.168.169.132:21': Connection refused
ftp: Can't connect to `192.168.169.132:ftp'
This was with the working machine plugged into the network but I have physical access so could use a copper connection if that would be better. This is where I am stuck.
If my plan fails and the damaged NMC still fails, there are instructions for how to start over using a serial connection. These are clear but I shall need help with using the USB to serial adaptor which I have but have no idea how to configure and then I have to root the machine!
If you have time helping me to ftp to the working machine please tell me where I should start as that would at least get me a copy of the working config.ini file.
Regards,
Budge.
Hi
Surely there is a way to restore from such a situation? Like a factory reset, recover from being bricked etc…?
Not found a factory reset but only one link on the APC website which seems hopeful:-
Video: Using Network Management Card 2 (NMC2) bootmonitor to recover/upgrade firmware
This requires using serial port connection. On further searching and reading I think I should go straight to this but will need help with setting up the USB-serial connection. It gives me the port parameters but finding which connection is the one on my laptop is a challenge. This is how it starts…
Resolution
The BootMonitor is roughly equivalent to the BIOS in a computer system. It offers users the ability to connect to it by using a serial communications cable. Once connected the user can query the BootMonitor for NMC related information, upload firmware files and reset/format the NMC by issuing relevant commands (a full list of commands is available in Appendix A at the end of this guide).
The following steps highlight how to connect to the NMC BootMonitor (Steps 1 - 3), how to reset the card to the default factory settings (Steps 4 - 5) and how to upload firmware files by using XMODEM (Steps 6 - 10).
I shall try and follow this and call for help when connected.
OK so all plugged in and using PuTTY but how do I find which connection to use. All I have offered so far is
/dev/ttyS0
. How do I find which is connecting to my USB port?
I think I have it with /dev/ttyUSB0. Will press on.
Not getting on very well. As soon as I touch the keyboard Putty closes. I presume I have the wrong settings or protocol. I have set serial to /dev/ttyUSB0 with the required Baud rate of 57600, 8 bits data, no parity, 1 stop bit no flow control. Then in Sessions screen I have selected Serial and enabled logging and enabled never close. I hope all the rest will use working defaults so have opened the application and that gives me a new black terminal window.
Getting the next bit right is where I fall down. The instructions say;-
- Press the Reset
button on the NMC (or reseat - unplug/replug the NMC back into the card slot) then immediately and consistently press the Enter key on the keyboard.>
As soon as I do that the Putty window closes. Poof!
Hi
So you can ping the ip address Yes or No?
If so have you tried the following Yes or No?
ssh -c 3des-cbc user@ipaddress
OK. All good after I found an FAQ which gave me the info I needed for a full manual installation. Nothing else APC advised worked and the “wizard” must have broken his wand! Fortunately the static IP I had set remained and I was able to install the three files needed using ftp.
It took me more time to find the right set of binaries because the APC filter system for downloads is rubbish and I had to wade through 40+ pages of download links until I found what has turned out to be an acceptable candidate. (My UPS is now well out of date and superseded by hundreds of more recent models).
However I am not quite at the happy ending because the NMC I borrowed turns out to be several points behind on the version numbers, so I want to upgrade this before I put it back whence it came.
My problem is that this NMC refuses my ftp connection thus:-
alastair@localhost:~> ftp 192.168.169.132
ftp: Can't connect to `192.168.169.132:21': Connection refused
ftp: Can't connect to `192.168.169.132:ftp'
ftp>
As far as I a concerned the cards are essentially identical with the same IP (only one is live) so what do I look for to get ftp access please? The Firewall etc has not been changed but I have done the work with the card plugged into my laptop nic, not over the network, which is what I did before.
All sorted now. There is a setting in the NMC config file for ftp which had not been enabled. Now all working fine and up to date.