How to disable emacs from trying to connect to a remote dir as you are typing?

When I'm typing a remote `:dir` value used in `org-babel` eg `/ssh:user@host:~` Emacs tries to make the connection automatically as though the directory is a local one. This results in repeated SSH connection attempts which in this case has resulted in `fail2ban` locking me out the server for a set duration. Is there some way to disable this behaviour? It should be able to distinguish a remote server from a local one and not attempt to connect to the remote unless requested eg `C-c C-c`.

I don't know, but it seems to me at the very least it should be caching the ssh connections. Probably hard to do without moving the ssh protocol into emacs.

There are ways to set the ssh config to [multiplex and reuse existing connections](https://www.tutorialspoint.com/how-to-use-openssh-multiplexer-to-speed-up-openssh-connections-on-linux). Then OP should be able to set a long enough timeout so reconnects are not made, or use a heartbeat connection.

I’m not sure, but this feels like it could be the fault of a “modern” completion framework polling for completions to display rather than Emacs itself. Just a hunch, not founded on anything.

That should happen by default though: `tramp-use-ssh-controlmaster-options`.

All sorts of things can cause excessive ssh activity. e.g. packages that augment your completing-reads, like `marginalia`, or `ivy-rich`. Also the likes of `projectile` sometimes goes off looking for project-root. You can get a lot of tramp debug information by setting `tramp-verbose` to 6 or higher and looking in the buffer `*debug tramp.*`. I identified where I could make some improvements by advising `tramp-send-command` to enter the debugger to catch it doing things I didn't want e.g.: (defun intercept-tramp-send-command (vec command &rest args) (when (string-match "\\(.projectile\\|/git\\)" command) (debug))) (advice-add 'tramp-send-command :before 'intercept-tramp-send-command) no

I don't think it is a caching issue. Say I'm typing `:dir /ssh:user@remote.com`. Emacs will try to connect to `/ssh:us@remote.com` before I finish typing. For some reason this didn't happen before. It started happening when I upgraded to Emacs 27 followed by another org upgrade.

Turn on the profiler and look at the call stack.

While this doesn't solve the problem on the Emacs side, setup keepalive for SSH connections and ensure multiplexing works. edit: I notice I gave no direct suggestion for how to do so. The multiplex controlmaster ControlPersist option is a good way to set this up reliably (see [ssh_config manual](https://www.man7.org/linux/man-pages/man5/ssh_config.5.html)).

Do you see this problem when you start with `emacs -Q` (no init file)? If not, bisect your init file to find the culprit. ---- A guess is that you're using some completion package that *automatically tries to complete input as you type it* (incremental completion), and that package (or at least the way you're using it) doesn't take into account trying to resolve remote file names. If so, it's *pedaling in the sauerkraut*, and maybe needs to be toned down a bit. ---- [Icicles](https://www.emacswiki.org/emacs/Icicles), for example, avoids this problem by automatically turning off incremental completion whenever a remote file name is read, that is, whenever your file-name input is likely to match a remote-file syntax. You can still complete remote file names. This turn-off just prevents eagerly going off automatically to remote locations to try to search for matching file names each time you type or remove an input character. ---- Standard function `file-remote-p` tests a file name for likelihood of being remote, without accessing anything remotely. Icicles uses this improved version of that function to deal with incremental completion: ;; NOTE: This is *not* a general substitute for `file-remote-p'. (defun icicle-file-remote-p (filename) "Non-nil means FILENAME is likely to name a remote file or directory. For MS Windows, if `icicle-network-drive-means-remote-flag' is non-nil then this includes a file on a mapped network drive. Otherwise, use `file-remote-p' if defined, or return nil if not. FILENAME is normally a string, but it can also be a cons whose car is a string. This is so that the function can be used to filter absolute file-name completion candidates." (when (consp filename) (setq filename (car filename))) (or (and (eq system-type 'windows-nt) (let ((case-fold-search t)) (string-match "\\`\\([a-z]:\\)" filename)) (eq 0 (condition-case nil (icicle-ms-windows-NET-USE (match-string 1 filename)) (error nil))) icicle-network-drive-means-remote-flag) (and (fboundp 'file-remote-p) (file-remote-p filename)) (and (stringp filename) (string-match "\\`/[^/]+:" filename) (match-string 0 filename)))) And there's also standard function `ffap-file-remote-p`: (defun ffap-file-remote-p (filename) "If FILENAME looks remote, return it (maybe slightly improved)." ;; (ffap-file-remote-p "/user@foo.bar.com:/pub") ;; (ffap-file-remote-p "/cssun.mathcs.emory.edu://dir") ;; (ffap-file-remote-p "/ffap.el:80") (or (and ffap-ftp-regexp (string-match ffap-ftp-regexp filename) ;; Convert "/host.com://dir" to "/host:/dir", to handle a dying ;; practice of advertising ftp files as "host.dom://filename". (if (string-match "//" filename) ;; (replace-match "/" nil nil filename) (concat (substring filename 0 (1+ (match-beginning 0))) (substring filename (match-end 0))) filename)) (and ffap-rfs-regexp (string-match ffap-rfs-regexp filename) filename)))

This was the same solution that I ended up using. I additionally used passphrase protected keys with ssh-askpass to ensure that it didn't abuse multiple SSH attempts.

Key or cert-based authentication is more convenient overall, on top of being more secure too.