host and jails csh login with "The terminal database could not be opened"

[bal0an]

I have made two changes to my TrueNAS instance:
1. upgrade NAS to 12.0-U4.1, and
2. upgrade some jails to 12.2-RELEASE-p6.
So when I login to my host with putty I now get below.
What is the correct way to fix the terminal?

Code:

Last login: Sat Jul 24 16:28:42 2021 from 192.168.178.67
FreeBSD 12.2-RELEASE-p6 df578562304(HEAD) TRUENAS

        TrueNAS (c) 2009-2021, iXsystems, Inc.
        All rights reserved.
        TrueNAS code is released under the modified BSD license with some
        files copyrighted by (c) iXsystems, Inc.

        For more information, documentation, help or support, go here:
        http://truenas.com
This is the PRIMARY NAS.

Warning: settings changed through the CLI are not written to
the configuration database and will be reset on reboot.

csh: The terminal database could not be opened.
csh: using dumb terminal settings.
root@nas1:~ # env
USER=root
LOGNAME=root
HOME=/root
PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/sbin:/usr/local/bin:/root/bin
MAIL=/var/mail/root
SHELL=/bin/csh
BLOCKSIZE=K
MM_CHARSET=UTF-8
LANG=en_US.UTF-8
TERM=putty-256color
SSH_CLIENT=192.168.178.35 51229 22
SSH_CONNECTION=192.168.178.35 51229 192.168.178.5 22
SSH_TTY=/dev/pts/1
HOSTTYPE=FreeBSD
VENDOR=amd
OSTYPE=FreeBSD
MACHTYPE=x86_64
SHLVL=1
PWD=/root
GROUP=wheel
HOST=nas1.fritz.box
REMOTEHOST=192.168.178.35
EDITOR=vi
PAGER=less

 

[Sean Hafeez]

So funny enough after my upgrade to TrueNAS-12.0-U6 I see the same issue when I ssh to the box. set term=xterm-256color fixes it for the session, but I have not tracked down why it started happening.

 

[Samuel Tai]

In PuTTY, try setting the terminal type under Connection->Data to just xterm, which is the default. Your server is just complaining it doesn't know what terminal type to use for putty-256color.

For all the supported terminal types, look in /usr/share/misc/termcap. There's an entry for putty as a clone of vt220-color.

 

[Sean Hafeez]

In my case the terminal I am connecting from is tmux-256-color. It is just strange as my git history shows me making that change a long time ago and this is the first time I have seen this when I connect.

 

[Samuel Tai]

Yup, no such terminal as tmux-256-color in the 12.0-U6 termcap. You can try this hint to set the term type before sshing: https://coderwall.com/p/ftuwdq/usin...ing-the-screen-256color-unknown-terminal-type