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I'm using rsync to connect and back up to a hard drive on a remote computer that I have ssh access to. rsync is connecting correctly. The code that's working is

rsync -av --progress -e "ssh -p port_number -i key/file/path" \
  "path/on/local/computer/to/back/up" \
  ssh_username@ssh_ip_address:"'path/on/remote/computer/to/back/up/to'"

I'm wondering if there is a way to get rsync to use its --log-file option to generate a log-file on the remote system (I want the file to be on the same remote hard drive that I'm backing up to). Any time I give it a remote path to use for the log-file (for example, with --log-file="path/on/remote/computer"), it seems to be looking for the path on my local system. I even tried --log-file=ssh_username@ssh_ip_address:path/on/remote/system, but it didn't work.

Is this possible, or do I need to make a log-file on the local system and then scp it to the remote system?

Both the local and remote systems are running Ubuntu 12.04.

share|improve this question
    
What OS are you using? It might be relevant. – terdon Feb 2 '13 at 19:34
    
@ terdon, ha, I edited my post with that information at the same time as you were commenting. I'm using Ubuntu 12.04 on both systems. – J L Feb 2 '13 at 19:36
up vote 1 down vote accepted

I would do the rsync to the other machine and then just run a scp command after to put the locally generated log file to the remote system where you'd like it kept.

rsyncing file + log

% rsync -avz -e 'ssh' $HOME/sample.sh remotemach:~ \
                --log-file=$HOME/rsync.log ; scp $HOME/rsync.log remotemach:~

confirming

% ls -l ~/rsync.log ~/sample.sh
-rwxrwxr-x 1 saml saml 10059 Oct 15 15:20 /home/saml/sample.sh
-rw-r--r-- 1 saml saml   192 Feb  2 14:57 /home/saml/rsync.log

% ssh remotemach "ls -l sample.sh rsync.log"
-rwxrwxr-x 1 saml saml 10059 Oct 15 15:20 sample.sh
-rw-r--r-- 1 saml saml   192 Feb  2 14:54 rsync.log

concatating the log to the remote side

If you'd like to concatanate the results from rsync to a remote file you can use a compound command (see bash's man page). Here I'm wrapping rsync with parens, and piping its output to ssh through a pipe, i.e.:

(rsync ...) | ssh ...

1st file copied

% (rsync -avz -e'ssh' $HOME/sample1.sh remotemach:~) \
                    | ssh remotemach "cat >> \$HOME/rsync.log"

confirm 1st copy

% ssh remotemach "ls -l sample*.sh rsync.log"
-rw-r--r-- 1 saml saml   133 Feb  2 19:49 rsync.log
-rwxrwxr-x 1 saml saml 10059 Feb  2 19:25 sample1.sh

2nd file copied

% (rsync -avz -e'ssh' $HOME/sample2.sh remotemach:~) \
                    | ssh remotemach "cat >> \$HOME/rsync.log"

confirm 2nd copy

% ssh remotemach "ls -l sample*.sh rsync.log"
-rw-r--r-- 1 saml saml   266 Feb  2 20:03 rsync.log
-rwxrwxr-x 1 saml saml 10059 Feb  2 19:25 sample1.sh
-rwxrwxr-x 1 saml saml 10059 Feb  2 19:25 sample2.sh

NOTE: Pay special attention to the file on the right side of the ssh. Notice that the $HOME path has a forward slash () in front of the $HOME. This is on purpose. It's necessary to escape the $HOME so that the local host's bash shell does not expand it.

share|improve this answer
    
@ slm, that makes sense. Thank you! What I would like to do is append the log-file to an existing log-file on the remote machine. Can scp append rather than overwrite a file? – J L Feb 2 '13 at 23:17
    
Following my question to @ slm above, I realized (following the post at linuxquestions.org/questions/linux-newbie-8/append-file-681666/…) that something like cat localfile | ssh user@remoteserver "cat >> remotefile" might work. – J L Feb 2 '13 at 23:31
    
I've expanded the answer to include a concatenation example as well. – slm Feb 3 '13 at 1:23
    
Thank you! That's very helpful! – J L Feb 3 '13 at 1:47
    
The compound command method gives you a way to accomplish what you were originally asking too. I didn't think of it until after. – slm Feb 3 '13 at 1:49

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