Bash script to ssh to particular server - bash

I'm wondering how I would go about creating my own bash script to ssh to a server. I know it's lazy, but I would ideally want not to have to type out:
ssh username#server
And just have my own two letter command instead (i.e. no file extension, and executable from any directory).
Any help would be much appreciated. If it helps with specifying file paths etc, I am using Mac OS X.

You can set configs for ssh in file ~/.ssh/config:
Host dev
HostName mydom.example.com
User myname
Then, just type
$> ssh dev
And you're done. Also, you can add your public key to the file ~/.ssh/authorized_keys so you won't get prompted for your password every time you want to connect via ssh.

Use an alias.
For example: alias sv='ssh user#hostname', then you can simply type sv.
Be sure to put a copy of the aliases in your profile, otherwise they will disappear at the end of your session.

you could create an alias like this:
alias ss="ssh username#server" and write it into your .bash_profile. ".bash_profile" is a hidden file is located in your home directory. If .bash_profile doesn't exist yet (check by typing ls -a in your home directory), you can create it yourself.
The bash_profile file will be read and executed every time you open a new shell.

You can use ssh-argv0 to avoid typing ssh.
To do this, you need to create a link to ssh-argv0 with the name of the host you want to connect, including the user if needed. Then you can execute that link, and ssh will connect you to the host of the link name.
Example
Setup the link:
ln -s /usr/bin/ssh-argv0 ~/bin/my-server
/usr/bin/ssh-argv0 is the path of ssh-argv0 on my system, yours could be different, check with which ssh-argv0
I have put it in ~/bin/ to be able to execute it from any directory (in OS X you may need to add ~/bin/ manually to your path on .bash_profile)
my-server is the name of my server, and if needed to set the user, it would be user#my-server
Execute it:
my-server
Even more
You can also combine this with mogeb answer to configure your server connection, so that you can call it with a shorter name, and avoid to include the user even if it is different than on the local system.
Host serv
HostName my-server
User my-user
Port 22
then set a link to ssh-argv0 with the name serv, and connect to it with
serv

Related

Get the remote bash shell to use a .bash_history file that is on my local machine

My environment contains clusters with multiple hosts in each cluster and as such I tend to run similar or equivalent commands on the hosts in such a cluster.
Sometimes, I am ssh-ed into a cluster host and remember that I had run a certain command on another host in this cluster but I can't remember which host I ran it on, however I need to run that command again.
Since every host in the cluster has its own .bash_history, I have to log in to each and every one of them and look through the .bash_history file to locate that command.
However, if I could use one .bash_history file for all hosts in the cluster (e.g. named .bash_history.clusterX) then I would be able to search the command in the bash history (with CTRL+R) and execute it.
Is that possible?
In my setup shared home directory (via nfs, etc.) is not an option.
Another approach is to leave the relevant commands to execute in an executable file ('ssh_commands') in the home folder of each remote user on each machine.
Those ssh_commands will include the commands you need to execute on each server whenever you open an SSH session.
To call that file on each SSH session:
ssh remoteUser#remoteServer -t "/bin/bash --init-file <(echo 'source ssh_commands')"
That way, you don't have to look for the right commands to execute, locally or remotely: your SSH session opens and execute right away what you want.

Synology default SSH login directory

When I connect to my Synology server via SSH, by default I get into the root directory. I want to change this to my home user folder. I am kind of able to do this via name#server 'cd /volume1/<user> ; bash', but then I get into a different bash interface compared to how I normally 1) log in via name#server and 2) then do cd /volume1/<user>. I would like to get the result of the latter, but than in the same line of code. What is the best method for doing this?

SCP file from ssh session to localhost

I have a headless file server on which I store and manage downloads and media, but occasionally I have to transfer small files back to my computer (Mac, using bash shell). The problem is that some files have more user-friendly names and commonly have spaces in them, and they are buried in the file directory hierarchy I have set up on my server.
When I'm using scp from my local machine, I don't have tab completion, so I have to manually type out the entire path and name with spaces escaped. When I ssh into the server first, the command:
scp /home/me/files/file\ name\ with\ spaces.png Me#localhost:/Users/Me/MyDirectory
fails with the error "Permission denied, please try again" even though I'm entering my local machine user password properly.
I've learned a little bit of sftp since I've been told that may be a better tool for file transfer. However, the utility seems outdated and I still don't have tab completion after establishing a connection to the server (on my Terminal when pressing Tab I just get a tab character).
My question is this: what can I do to allow tab completion while using scp from my Mac? Or am I using incorrect syntax for scp while in an ssh session, and is there something in that command I should fix? Or, is there a (better? newer?) tool other than sftp that would offer tab completion on a server?
Finally, if none of these problems have simple solutions, is there some package I could install (e.g. a completion package from Homebrew or the like) that would facilitate better tab-completion with any of these commands?
Looks to me like this is some incorrect scping.
This is the format of the command
scp ./localFile.txt remoteUser#remoteHost:/remoteFile.txt
You were so close, but you have localhost set where you should have your remoteHost.
localhost is the name that resolves to the machine that you are currently on - so in your workflow, you are sshing to a machine, and then trying to scp that file to the same machine you are already sshd into.
What you need to do, is figure out the IP address, or the physical host name of the computer that you are trying to connect to, and use that instead.
scp ./localFile.txt remoteUser#192.168.1.100:/remoteFile.txt
# where 192.168.1.100 would be the IP of your Mac
I am assuming the reason you were getting permission denied, was because you were using your the login credentials for you mac, but unknowingly trying to login again to your headless machine.

Opening a remote file with TextWrangler

My current solution for editing files on a remote web server is to use Fetch to browse the remote machine and TextWrangler to make the edits. But since I'm getting more comfortable navigating the command line on the remote machine (but not comfortable enough to use VIM...), I'd like to be able to type something like 'open filename.txt' on the remote machine and have TextWrangler open up on my local machine. I've heard the term "reverse tunneling" tossed around as an option, but I have no idea what to do next. Any suggestions are greatly appreciated - thanks!
Personally, I use Cyberduck as my S/FTP browser. In Cyberduck's preferences, you can define a default text editor to edit remote files. Now I can just hit Cmd+K when I have a file selected, and it will open up in TextWrangler. Whenever I save, the changes are automatically transferred to the remote file.
I was actually looking to do the same thing, and no one had written it up, so I figured this out today.
There's 2 required and 3 optional parts to this:
Enable ssh login on both computers (required)
Set up an ssh tunnel from the remote machine to your machine (required)
Set up an alias for the ssh tunnel (optional)
Set up an alias for TextWrangler on the remote machine (optional)
Set up ssh keys so you don't have to enter your password every time (optional)
You need to be able to ssh from local to remote to run the commands, and you need to be able to ssh from remote to local so it can send commands to TextWrangler.
To set up the ssh tunnel, you need to run a command on your local machine like:
ssh -f -N -R 10022:localhost:22 [username on remote machine]#[remote machine hostname]
The -f and -N flags put ssh into the background and leave you on your machine. The -R flag binds a port on the remote computer to a port on your local computer. Anything contacting the remote machine on port 10022 will be sent to port 22 on your local computer. The remote port can be anything you want, but you should choose a port > 1024 to avoid conflicts and so you don't have to be root. I chose 10022 because it's similar to ssh's default port of 22. Replace the brackets with your username and machine name.
You'll need to run that once after you log in. To make the command easier on yourself, you can add an alias in your bash profile. Add the following to your local ~/.bash_profile:
alias open-tunnel='ssh -f -N -R 10022:localhost:22 [username on remote machine]#[remote machine hostname]'
Of course, you can choose whatever alias name you like.
Once you've set up the tunnel, you can use a command like this on the remote machine:
ssh -p 10022 [username on local machine]#localhost "edit sftp://[username on remote machine]#[remote machine hostname]//absolute/path/to/file.txt"
The -p flag says to use port 10022 (or whichever port you chose earlier). This will cause the remote machine to connect to your local machine and execute the command in the double quotes without opening an interactive ssh session. The command in the quotes is the command you would run on your local machine to open the remote file in TextWrangler.
To make the command easier on yourself, you can add a function in your bash profile. Add the following to your remote ~/.bash_profile:
function edit { if [[ ${1:0:1} = "/" ]]; then abs_path="$1"; else abs_path="`pwd`/$1"; fi; ssh -p 10022 [username on local machine]#localhost "edit sftp://[username on remote machine]#[remote machine hostname]/$abs_path"; }
This is assuming that you don't have the TextWrangler command line tools installed on the remote machine. If you do, you should name the function something other than edit. For example, tw. Here, ${1:0:1} looks at the first character of the first parameter of the function, which should be the file path. If it doesn't begin with /, we figure out the absolute path by adding the current working directory (pwd) to the beginning. Now, if you're on the remote machine in /home/jdoe/some/directory/ and you run edit some/other/directory/file.txt, the following will be executed on your local machine:
edit sftp://[username on remote machine]#[remote machine hostname]//home/jdoe/some/directory/some/other/directory/file.txt
Lastly, you should set up ssh keys in both directions so you're not prompted for a password every single time. Here's a guide someone else wrote: http://pkeck.myweb.uga.edu/ssh/
I dont think this will allow opening from the command-line, but
Eclipse with Remote-System-Explorer also supports editing of files via ssh connection
I think what you're referring to is called "X11 forwarding" over ssh. Take a look at the ssh_config(5) manpage for configuration (or just use 'ssh' with the '-X' parameter). As far as i know, this does only work with X11 programs (gvim, xemacs, etc.), because the editor is actually running on the host you're connecting to - only the display stuff happens on your local machine. So TextWrangler is not an option, because it's not an X11 program.
I use Interarchy (from nolobe) for remote editing. It's a fairly advanced ftp/sftp client that gives you a finder-style view of your remote files and allows you to use your favourite editor to work on those files.
If you don't like to pay for such a program, there's an Open-Source program called "Fugu" available from the Univerity of Michigan which you can also use.
FileZilla offers this functionality as well. You can download it here. Once you've connected to your sftp you can right-click on the text file and open it with the text editor of your choice.
Minimal answer
You can use Applescript. So from the command line execute this:
osascript <<EOF
tell application "TextWrangler"
activate
open location {"sftp://myusername:#my.server:22222//home/username/.bashrc"}
end tell
EOF
Notes
Obviously you wouldn't want to type a here document on every invocation, so my suggestion would be to put this logic inside a regular shell script:
osascript <<EOF
tell application "TextWrangler"
activate
open location {"$1"}
end tell
EOF
Then invoke the script like this:
sh ~/bin/textwrangler.sh "sftp://myusername:#my.server:22222//home/username/.bashrc"
Specifying a host-qualified path can get tedious each time so either hardcode that in your script, or bind the script invocation to a keystroke via your shell. For bash:
bind '"\et":"sh ~/bin/textwrangler.sh \"sftp://myusername:#my.server:22222/\""'
Now you generate the majority of the command by pressing Alt-t

Moving a folder from Desktop to the server?

I have a folder in my Desktop. I want to copy it to my server in Terminal.
I tried this unsuccessfully
[~/bin]# cp -r /Users/Sam/Desktop/tig-0.14.1 ~/bin/
cp: cannot stat `/Users/Sam/Desktop/tig-0.14.1': No such file or directory
[edit]
I run the command in my server. The problem seems to be in the fact that "/Users/Sam/Desktop/tig-0.14.1" is a folder in my Mac, not in my server.
Perhaps, I cannot move the folder so simply to my server because my server do not know where my folder locates.
I have always moved the folder by GUI. Is the same possible also just in terminal?
From the server:
scp -r username#A.B.C.D:~/Desktop/tig-0.14.1/ ~/bin/
username is your shortname on your local mac.
A.B.C.D is the IP address of your local mac as seen by the server.
You will be prompted for your password.
Or if you wanted to push from your local client:
scp -r ~/Desktop/tig-0.14.1/ serveruser#W.X.Y.Z:~/bin/
serveruser is the user on the server whose ~/bin you want to copy into.
W.X.Y.Z is the IP address of the server as seen by your client.
You will be prompted to enter serveruser's password.
scp is part of ssh. See 'man scp' (from the terminal) for more info.
From your Mac (not the server):
# scp -r ~/Desktop/tig-0.14.1 myUsername#myServerName:~/bin
replace myUsername and myServerName appropriately.
cp is not the correct command. Try scp instead; it has similar use and you can use it like this: (see the manual for reference)
from linux client:
scp user1#host1://Users/Sam/Desktop/tig-0.14.1 ~/bin/
if you use a windows client you can use winscp to do this in "drag&drop" style
cp: cannot stat/Users/Sam/Desktop/tig-0.14.1': No such file or directory`
That's the problem, alright: the file you're trying to copy is not where you thought, or not named what you typed. As suggested in comments you can try using tab completion at the prompt to make sure you have everything correct:
# cp /Users/Sam/Desk<TAB>
# cp /Users/Sam/Desktop/tig<TAB>
# cp /Users/Sam/Desktop/tig-0.14.1.tar.gz
Note that tig-0.14.1.tar.gz is probably the actual file name, as found in the wild...

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