When trying to open a file through ssh in emacs, I got an error:Couldn't find a POSIX `id' command
QUESTION: What is the problem?
Does your remote system has proper id command? You can verify what TRAMP is trying to do if you set
(setq tramp-verbose 10)
Then try to connect and monitor buffers *tramp/...* and *debug tramp/...*. If the remote path does not get set correctly by TRAMP, you can change it:
(add-to-list 'tramp-remote-path "/path/to/id/command")
This just happened to me recently for the first time... after never having the issue before on the same cluster of servers. It ended up being that the server I was trying to connect to was out of disk space...and this error was just a side effect of that. So it's worth doing a df -h if this issue seems to come out of nowhere.
Related
I've having serious trouble using tramp on Emacs. I am continuously being asked for my password when I ssh into a server via tramp. This is to the point where it blocks me being able to do anything.
I have looked far and wide on the internet and the most widely used solutions do not seem to work for me.
I have Emacs 24.*
I have (setq password-cache-expiry nil)
I have (setq projectile-mode-line " Projectile")
Here is my tramp setup in my .emacs.d for the curious http://pastebin.com/NJCaa0RH.
Has anyone else had this problem and can point me in the way of a fix? Or do you see a glaring error in tramp config?
Make sure you can login via keys instead of password. This would involve copying ~/.ssh/id_rsa.pub or ~/.ssh/id_ed25519.pub from your local machine and pasting the same in ~/.ssh/authorized_keys on the server
Having a ssh config should help simplify the syntax
Having a persistent connection would also help with your problem
(customize-set-variable
'tramp-ssh-controlmaster-options
(concat
"-o ControlPath=/tmp/ssh-ControlPath-%%r#%%h:%%p "
"-o ControlMaster=auto -o ControlPersist=yes"))
I am running graphical Emacs 24.3.1 (this problem exists when using the console version as well) on Arch Linux. I am trying to use TRAMP to open files on a remote Fedora system by SSH with a private key which requires a password. Authentication works fine, and so does the listing of files. When I do try to open a file, my Emacs session hangs with "Tramp: Inserting `/{filename I'm trying to open}' ...done". It is not possible to abort with ESC ESC ESC or C-g. Does anyone have a solution to this?
Emacs 24 normally works very well with Tramp. What you might need is ControlMasterAuto in your .ssh/config file. This will ensure that the ssh connection information passes seamlessly to Emacs. This will also ensure that you only need to login once in a terminal and use multiple emacs frames in tramp mode. I have detailed the following steps
(1) Go to your .ssh/config file and add the following options
Host <hostname>
ControlMaster auto
ControlPath ~/.ssh/%r#%h:%p
ServerAliveCountMax=30
ServerAliveInterval=5
(2) Now login to the remote host through terminal.
(3) Open emacs frame and try opening the remote files through tramp (/ssh:). You must be able to connect to the remote host.
The above steps should work even for a two level authentication (using a rsa key +password).
This thread is old - however, a very similar problem on my FC22 laptop (tramp hanging when trying to type a colon following /su in the minibuffer) appears to be fixed by commenting the ::1 line in /etc/hosts.
I'm trying to use Tramp/Emacs-23 in Ubuntu 12.04 in order to edit the remote host files. My remote host has two step authentication (RSA+Passwd). I use multiplexing through .ssh/config to ensure that tramp can directly connect to the remote shell without having to provide passwords.
My problem however is that I have 3 different remote hosts. When I try to connect to remote host through tramp without the initial multiplexing (through terminal), the TRAMP hangs with a message stating "Tramp: Waiting for prompts from remote shell". I used the below mentioned commands in .ssh/config to ensure the connection gets lost after a specified interval upon no prompt.
Host *
ServerAliveCountMax=30
ServerAliveInterval=5
However this doesn't seem to have any effect on the tramp connection. It will be of help if someone can help me in fixing this issue.
Sorry that your question has been left hanging so long.
I can offer a couple of things to try, use the tramp protocol sshx instead of ssh, it seems to cope better with most non-vanilla ssh connections.
e.g.
/sshx:user#host:path/filename
The other thing to try is adding your ssh key passphrase to the session at startup, run an ssh-agent on the machine, and connect to it at startup, then run ssh-add to enter the passphrase once.
As a side note, upgrade your Emacs to 24.3 there's a lot of new/great stuff in there since 23.x
I want to open a file inside Emacs which is located on a remote server, with sudo powers on the server. I can open local files with sudo via Tramp like this:
C-x C-f /sudo::/home/user/file
But I want to use sudo on the server:
C-x C-f /sudo::user#server/home/user/file
But this gives me sudo powers on my local machine, it asks for my sudo password on the local machine. Is there a way to use sudo on the server?
BTW: Emacs is not installed on the server
As of Emacs 24.3, an analog of the old multi: syntax has been layered on top of the modern tramp-default-proxies-alist approach, meaning that you can once again perform multi-hops without any prior configuration. For details, see:
C-hig (tramp)Ad-hoc multi-hops RET
With the new syntax, each 'hop' is separated by |. The example in the manual is:
C-xC-f /ssh:bird#bastion|ssh:you#remotehost:/path RET
Which connects firstly as bird#bastion, and from there to you#remotehost:/path
/su: or /sudo: on remote hosts
You can also use this syntax to sudo/su to root (or of course any other user) on a remote host:
C-xC-f /ssh:you#remotehost|sudo:remotehost:/path/to/file RET
Important: be sure to specify the hostname explicitly: sudo:remotehost: rather than sudo:: (see below).
As this still uses the proxy mechanism underneath, tramp-default-proxies-alist should now include the value ("remotehost" "root" "/ssh:you#remotehost:")
Meaning that the proxy /ssh:you#remotehost: is going to be used whenever you request a file as root#remotehost.
root is the default user for these methods, but you can of course also change to a non-root user with:
C-xC-f /ssh:you#remotehost|sudo:them#remotehost:/path/to/file RET
Always specify the remote hostname explicitly
You are probably used to using sudo:: or su:: and omitting the hostname. If you are staying on the localhost then this is still fine, but if you are hopping to a remote server then you must specify the hostname for every hop -- even if it is the same as for the previous hop. Always use sudo:hostname: or su:hostname: with remote hosts.
The trap here is that sudo:: does actually appear to work -- however when you do that the HOST for the dynamic proxy entry will be the hostname you originated from rather than the host you connected to. This will not only look confusing (as the wrong host will be displayed in the file paths), but it will also mean that any subsequent attempt to use sudo:: on your localhost will instead be proxied to the remote server! (and the proxy would also presumably be clobbered if you did the same thing on a second server, causing further issues).
In short, don't use :: when you multi-hop!
Emacs 27+
Starting from Emacs 27.1 (or Tramp 2.4.2, if using the GNU ELPA package) the :: case works intuitively, such that /ssh:you#remotehost|sudo:: will re-use remotehost rather than your own local host, and so you won't end up with a bad proxy entry.
In addition, the likes of /ssh:you#remotehost|sudo:localhost: are detected and flagged as user errors.
If you are liable to use a mixture of Emacs versions including versions earlier than 27 (or you are advising someone else who may be using an older version), then it would be safest to continue to treat :: as unsafe when multi-hopping, to avoid potential mishap. (I.e. specifying the correct remote host explicitly will remain the safest approach if the Tramp version is unknown.)
Update: Although this answer solved the original problem, it was written for emacs 20 or 21. For emacs 24, I recommend you use phils's answer because it offers more explanation and is up to date.
I think multi-hop filenames in tramp is what you're looking for.
The first hop would be ssh and the second would be sudo.
Update: Recent versions of emacs support multiple hops using proxies:
(add-to-list 'tramp-default-proxies-alist ("my-sudo-alias" nil "/ssh:user#ssh-host"))
Then invoke by opening:
/sudo:my-sudo-alias:file-on-ssh-host
I had some troubles with the selected answer. However, it worked when I added this line to .emacs:
(add-to-list 'tramp-default-proxies-alist '(".*" "\\`root\\'" "/ssh:%h:"))
And then executed the following:
/sudo:ssh-host:file-on-ssh-host
It was slightly confusing because at one point I was prompted for the "root" password, but entering my user's password granted me access. It also universally works on all hosts on the network. Also, I can still do this to not be root:
/ssh:ssh-host:file-on-ssh-host
From the tramp multi-hops configuration webpage
(add-to-list 'tramp-default-proxies-alist
'(nil "\\`root\\'" "/ssh:%h:"))
(add-to-list 'tramp-default-proxies-alist
'((regexp-quote (system-name)) nil nil))
Then any
C-x C-f /sudo:remote-host:/file
will open file using sudo after logged with the same username of the user running emacs but on the remote machine.
You have to ssh into the server first, then you have to run emacs locally.
Or you can use NFS with no_root_squash, or you can try with emacs server/client, although I have no idea of what may happen (do not use emacs myself)
I would like to be able to use Matlab-mode (matlab.el) to run a matlab shell. The only problem is, Matlab is located on a remote host. Is this even possible? If so, please explain. I'm currently playing around with tramp but to no avail.
Thanks.
I just tried using the emacs matlab mode through ssh, no problem
had to make a script which loads matlab, couldn't just specify the command in matlab.el
so:
/home/second/remoteMatlab:
#!/bin/bash
ssh orac matlab -nodisplay
where orac is the host which has matlab. you can pass commands to ssh here. i use ssh config and key authentication so only need the hostname here
in matlab.el, find
(defcustom matlab-shell-command
and set to eg
(defcustom matlab-shell-command "/home/second/remoteMatlab"
I am not 100% sure what you are doing, but this seems possible. If
you use Tramp (or sshfs, my personal choice) to edit a script on a
remote machine, you will be able to run it on that remote machine. If
you have a *shell* buffer open, it can easily be ssh'd to that remote
machine. If you are doing something REPL-like where emacs sends input
to this buffer that's connected to a process over ssh, it should still
work. If it is communicating with a remote process over a socket, you
can use ssh forwarding to make the socket appear local.
Anyway, there is not much gap between local and remote, so this should
all work out.
Finally, to toe the (GNU) party line... have you tried Octave running locally?
#Yotham : I can't comment yet on earlier answers, but your problem (Script working, malab-shell command in emacs not) may be due to the fact that you didn't delete/rename your matlab.elc file?
This way emacs never gets to know of the change since it prefers .elc over .el files for speed.
Resolved the same issue for me.
cheers
tnt