Troubleshooting SSH agent items

[troffasky]

I am trying to use an SSH agent item to log in to a Sonicwall firewall and fetch some data. I am struggling to even connect at all. According to a packet capture on the firewall, no connection is even attempted. Yes, I can ssh to the target from the proxy without issue.
Key:
ssh.run[snwlblob]
note - no options actually set.
Auth method: Password.
User/pass are both usermacros.

Error is: "Cannot set SSH session options: Invalid argument in ssh_options_set"

Logs from proxy:

27225:20250711:180435.892 In get_value() key:'ssh.run[snwlblob]'
27225:20250711:180435.892 In ssh_run()
27225:20250711:180435.892 End of ssh_run():NOTSUPPORTED
27225:20250711:180435.892 Item [:ssh.run[snwlblob]] error: Cannot set SSH session options: Invalid argument in ssh_options_set

AFAICT I have the only mandatory option set - the description. All others are optional. So why is it complaining?

Why a proxy? Because I could not work out which subsystem to increase the debug level for in order to see what the server is doing. So I have spun up a proxy just for this!

[troffasky]

OK, looks like the previous error is actually only when using the "Test" button in the item configuration! If I use 'Execute now' instead, I get:

27226:20250711:182556.824 In substitute_key_macros_impl() data:'ssh.run[snwlblob]'
27226:20250711:182556.824 End of substitute_key_macros_impl():SUCCEED data:'ssh.run[snwlblob]'
27226:20250711:182556.824 In get_value() key:'ssh.run[snwlblob]'
27226:20250711:182556.824 In ssh_run()
27226:20250711:182556.980 ssh_run() supported authentication methods: password
27226:20250711:182556.988 ssh_run() password authentication succeeded
27226:20250711:182558.053 End of ssh_run():NOTSUPPORTED
27226:20250711:182558.053 Item [Sonic test SSH:ssh.run[snwlblob]] error: Cannot request a shell: Socket error: disconnected

What does this mean? If I Google it, I come back to this thread from 2021:

https://www.zabbix.com/forum/zabbix-help/418309-cannot-request-a-shell

which seems to be the last time I was testing this. No progress in 4 years!

[troffasky]

If I test with "normal" SSH client, it looks like it "requests a shell" and succeeds:

[email protected]'s password:
debug3: send packet: type 50
debug2: we sent a password packet, wait for reply
debug3: receive packet: type 52
Authenticated to 10.10.10.10 ([10.10.10.10]:22) using "password".
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug2: channel 0: send open
debug3: send packet: type 90
debug1: Requesting [email protected]
debug3: send packet: type 80
debug1: Entering interactive session.
debug1: pledge: filesystem
debug3: receive packet: type 80
debug1: client_input_global_request: rtype [email protected] want_reply 1
debug3: send packet: type 82
debug3: receive packet: type 91
debug2: channel_input_open_confirmation: channel 0: callback start
debug2: fd 3 setting TCP_NODELAY
debug3: set_sock_tos: set socket 3 IP_TOS 0x10
debug2: client_session2_setup: id 0
debug2: channel 0: request pty-req confirm 1
debug3: send packet: type 98
debug1: channel 0: setting env LANG = "en_GB.UTF-8"
debug2: channel 0: request env confirm 0
debug3: send packet: type 98
debug2: channel 0: request shell confirm 1
debug3: send packet: type 98
debug2: channel_input_open_confirmation: channel 0: callback done
debug2: channel 0: open confirm rwindow 0 rmax 32768
debug3: receive packet: type 99
debug2: channel_input_status_confirm: type 99 id 0
debug2: PTY allocation request accepted on channel 0
debug2: channel 0: rcvd adjust 2097152
debug3: receive packet: type 99
debug2: channel_input_status_confirm: type 99 id 0
debug2: shell request accepted on channel 0