ssh localhost succeeds:
neptune% ssh localhost
Linux neptune 5.16.0-0.bpo.4-amd64 #1 SMP PREEMPT Debian 5.16.12-1~bpo11+1 (2022-03-08) x86_64
The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.
Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
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Last login: Sat Jun 18 21:11:19 2022 from ::1
neptune%
C-x C-f /ssh:localhost:~/ gets stuck in a loop and fails.
I am not sure whether this is failure to detect the shell prompt, as described here: How to debug hanging tramp connections? (this did not solve it: https://emacs.stackexchange.com/a/45810/6682)
After setting tramp-verbose higher, I see in the logs:
;; Emacs: 28.1 Tramp: 2.5.2.28.1 -*- mode: outline; coding: utf-8; -*-
18:04:10.075003 tramp-maybe-open-connection (3) # Opening connection nil for localhost using ssh...
18:04:10.077807 tramp-maybe-open-connection (3) # Sending command ‘exec ssh -o ControlMaster=auto -o ControlPath='tramp.%C' -o ControlPersist=no -e none localhost’
18:04:10.078022 tramp-process-actions (3) # Waiting for prompts from remote shell...
18:04:10.078228 tramp-process-one-action (5) # Looking for regexp "\(.*\(user\|login\)\( .*\)?: *\)\'" from remote shell
18:04:10.078405 tramp-process-one-action (5) # Looking for regexp "\(^.*\(\(?:adgangskode\|contrase\(?:\(?:ny\|ñ\)a\)\|decryption key\|encryption key\|geslo\|h\(?:\(?:asł\|esl\)o\)\|iphasiwedi\|jelszó\|l\(?:ozinka\|ösenord\)\|m\(?:ot de passe\|ật khẩu\)\|p\(?:a\(?:rola\|s\(?:ahitza\|s\(?: phrase\|code\|ord\|phrase\|wor[dt]\)\|vorto\)\)\|in\)\|s\(?:alasana\|enha\|laptažodis\)\|wachtwoord\|лозинка\|пароль\|ססמה\|كلمة السر\|गुप्तशब्द\|शब्दकूट\|গুপ্তশব্দ\|পাসওয়ার্ড\|ਪਾਸਵਰਡ\|પાસવર્ડ\|ପ୍ରବେଶ ସଙ୍କେତ\|கடவுச்சொல்\|సంకేతపదము\|ಗುಪ್ತಪದ\|അടയാളവാക്ക്\|රහස්පදය\|ពាក្យសម្ងាត់\|パスワード\|密[码碼]\|암호\)\).*:\0? *\)\'" from remote shell
18:04:10.078614 tramp-process-one-action (5) # Looking for regexp "\(^.*\(Connection \(?:\(?:clo\|refu\)sed\)\|Host key verification failed\.\|Login \(?:[Ii]ncorrect\)\|N\(?:ame or service not known\|o supported authentication methods left to try!\)\|Permission denied\|\(?:Sorry, try again\|Timeout, server not responding\)\.\).*\|^.*\(Received signal [[:digit:]]+\).*\)\'" from remote shell
18:04:10.078776 tramp-process-one-action (5) # Looking for regexp "\(^[^#$%>
]*[#$%>] *\)\'" from remote shell
18:04:10.078926 tramp-process-one-action (5) # Looking for regexp "\(\(?:^\|
\)[^]#$%>
]*#?[]#$%>] *\(\[[[:digit:];]*[[:alpha:]] *\)*\)\'" from remote shell
18:04:10.079059 tramp-process-one-action (5) # Looking for regexp "\(\(Are you sure you want to continue connecting (yes/no\(?:\(?:/\[fingerprint]\)?)\?\)\)\s-*\)\'" from remote shell
18:04:10.079190 tramp-process-one-action (5) # Looking for regexp "\(\(\(?:Store key in cache\? (y/\|Update cached key\? (y/n, Return cancels connectio\)n)\)\s-*\)\'" from remote shell
18:04:10.079316 tramp-process-one-action (5) # Looking for regexp "\(\(TERM = (.*)\|Terminal type\? \[.*\]\)\s-*\)\'" from remote shell
18:04:10.079437 tramp-process-one-action (5) # Looking for regexp "\(Access granted\. Press Return to begin session\. \)\'" from remote shell
18:04:10.079565 tramp-process-one-action (5) # Looking for regexp "\(^
*Confirm user presence for key .*[
]*\)\'" from remote shell
18:04:10.079682 tramp-process-one-action (5) # Looking for regexp "\(\)\'" from remote shell
18:04:10.079808 tramp-process-one-action (5) # Call ‘tramp-action-process-alive’
.
.
.
.
[log after C-g which cancels the TRAMP connection]
[1m[7m%[m[1m[m
]2;peterbecich@neptune:~]1;~
[m[m[m[Jneptune% [K[?2004h
18:04:16.233084 tramp-accept-process-output (1) # Quit: "Quit", ""
Linux neptune 5.16.0-0.bpo.4-amd64 #1 SMP PREEMPT Debian 5.16.12-1~bpo11+1 (2022-03-08) x86_64
The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.
Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
You have new mail.
Last login: Sat Jun 18 18:04:00 2022 from 127.0.0.1
[1m[7m%[m[1m[m
My default shell is zshell:
neptune% echo $SHELL
/bin/zsh
Oddly, the shell shown in the log message above appears to be bash; perhaps that is a clue:
neptune% bash
peterbecich@neptune:~$
TRAMP fails to log into localhost regardless of how explicit-shell-file-name is set: https://superuser.com/questions/454288/how-to-specify-for-emacs-tramp-which-remote-shell-to-open
TRAMP succeeds at logging into a Vagrant box:
/ssh:[email protected]:/home/vagrant:
total used in directory 16K available 16.2 GiB
drwx------ 1 vagrant vagrant 112 Aug 11 2019 .
drwxr-xr-x 1 root root 14 Aug 5 2019 ..
-rw------- 1 vagrant vagrant 189 Jun 19 03:53 .bash_history
-rw-r--r-- 1 vagrant vagrant 21 Apr 30 2019 .bash_logout
-rw-r--r-- 1 vagrant vagrant 57 Apr 30 2019 .bash_profile
-rw-r--r-- 1 vagrant vagrant 141 Apr 30 2019 .bashrc
drwx------ 1 vagrant vagrant 12 Aug 11 2019 .config
drwx------ 1 vagrant vagrant 30 Aug 11 2019 .ssh
I'm attempting to log into localhost with TRAMP in order to reproduce an unrelated issue.
