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Cat a file across ssh?


 
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# 1  
Old 02-12-2013
Question Cat a file across ssh?

There is a file on a remote host that I want to read across an ssh tunnel. NOT copy... scp won't work here. And this file requires elevated permissions to read.

'ssh -t remotehost sudo cat /path/to/file' will prompt me for my sudo password and read out the file. But I'm coming up blank for a way to capture that output. I really just need to grep and cut and sed my way through the output, so it doesn't matter how the content is available locally... writing to a temporary file is fine, or just streaming it across. But requiring the password to be entered puts the kybosh on every way of piping or redirecting the output I can think of. I can probably use a tar pipe to get it across, but it seems there ought to be an easier way to do this.
# 2  
Old 02-12-2013
Actually, the password prompt shouldn't care about redirection, since it goes to the terminal, not stdout specifically.

Ordinary shell redirection should work, I think.

Code:
ssh -t -t remotehost sudo cat /path/to/file > /path/to/localfile

# 3  
Old 02-12-2013
Suppose you could try writing it to stderr:

Code:
ssh -t -t remotehost 'sudo cat /path/to/file >&2' 2> /path/to/localfile

# 4  
Old 02-12-2013
I cheated a little bit... Smilie

ssh -t $host 'sudo -v'

And then I was able to read my file with sudo but without the password.
This User Gave Thanks to jnojr For This Post:
# 5  
Old 02-12-2013
Be carefull that sudo isn't just using cached credentials, you may find that if you wait 5 mins sudo will require a password (unless you are allowing passwordless sudo for this user/command combo)

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