I'm mounting sd_image.bin image which was formatted as FAT (mkfs.fat) into sd_drv directory, like this:
mkdir sd_drv
sudo mount -t vfat -o loop sd_image.bin sd_drv -o rw,uid=$(id -u),gid=$(id -g)
This works well.
However, an application is also accessing sd_image.bin (reads/writes files and creates new files in that file-system image). It does so while sd_image.bin is mounted to sd_drv.
When I'm examining files at sd_drv mount point I still see its old contents and not the updated content which was updated by the application, as if Linux is caching the filesystem.
On the other direction I see the same problem - when I'm updating sd_drv, the application does not "see" my updates on sd_image.bin.
Is there a way to prevent this caching and allow sd_drv to reflect the contents of sd_image.bin immediately?
If not, is there some way to refresh sd_drv and make it sync with sd_image.bin without unmounting/remounting it?
(It's safe to assume that modifications to sd_image.bin and to sd_drv are not done simultaneously)
Related
Upon my initial looking both cp and rsync will copy an entire directory structure.
That being said, what is the purpose for each and which is better?
cp -R $source $destination
vs
rsync -auq $source $destination
I was trying to look into and figure this out more, but they both seemed to copy an entire directory around the same speed.
Does one leverage another? When cloning someone's HD which is the best course of action and why?
I think the main purpose of rsync not to copy directory from to the same system or machine It efficiently copies and sync files to or from a remote system.
Remote system like two different machines
and if you need the difference if you use them locally see this link
I have iPython Notebook through Anaconda. I accidentally deleted an important notebook, and I can't seem to find it in trash (I don't think iPy Notebooks go to the trash).
Does anyone know how I can recover the notebook? I am using Mac OS X.
Thanks!
This is bit of additional info on the answer by Thuener,
I did the following to recover my deleted .ipynb file.
The cache is in ~/.cache/chromium/Default/Cache/ (I use chromium)
used grep in binary search mode, grep -a 'import math' (replace search string by a keyword specific in your code)
Edit the binary file in vim (it doesn't open in gedit)
The python ipynb should file start with '{ "cells":' and
ends with '"nbformat": 4, "nbformat_minor": 2}'
remove everything outside these start and end points
Rename the file as .ipynb, open it in your jupyter-notebook, it works.
The "delete" functionality now sends the file to OS trash rather than permanently deleting it, see this PR: https://github.com/jupyter/notebook/pull/1968. So you can just open your Trash (wherever that is on your system) and restore it.
I think the easiest way (until developers handle this issue) to retrieve your Ipython history is to write them all into an empty file.
You need to check by the date you created your last script. Obviously, it is going to be the last part of your Ipython history.
To write your Ipython history into a file:
%history -g -f anyfilename
On linux:
I did the same error and I finally found the deleted file in the trash
/home/$USER/.local/share/Trash/files
If you deleted it through the OS (rm file.ipynb) then you can probably get it from ~/.ipython_checkpoints/ However, if you deleted it from the browser menu option, it is gone (by design!).
See discussion here: https://github.com/jupyter/notebook/issues/405
If you use PyCharm, you can do the following.
Open the Local History view.
Select the version you want to roll back to.
On the context menu of the selection, choose Revert.
Worked for me!
Source: here
For the unlucky ones like me, that delete some files on JuliaBox(jupyter for julia), there is a solution. I successifly recovery all my deleted files.
The browsers strore cache information about the pages you visit. You have to find your cache browser folder (in ubuntu with crhome was ~/.cache/google-chrome/Default/Cache) and grep for some text of your notebook in the binarys. Then, cut the text part of the file that is correspond to your ipynb.
https://groups.google.com/forum/#!searchin/julia-box/delete%7Csort:relevance/julia-box/Rt9LG9RldrU/3s_vVSrivJEJ
If you're using windows, it sends it to the recycle bin, thankfully. Clearly, it's a good idea to make checkpoints.
As long as your Kernel is active, the code of each executed cell is stored in input history list. This will come in handy when you accidentally deleted a cell and want to retrieve its content.
_ih[-10:] *# code of the 10 most recently run cells (Even if those cells are deleted now)*
If you are running on Jupyterlab on linux like me. What I did is went into command prompt and went to my trash folder.
Trash directories on linux are typically
/home/$USER/.local/share/Trash
or
If you deleted something as root (e.g. deleted a file using Nautilus invoked via gksu), it is at
/root/.local/share/Trash
I ended up changing directories to /home/$USER/.local/share/Trash/files and my deleted notebook was there! depending on how you access your backend you could also try /home/jupyter/.local/share/Trash/
ps
If you are having issues changing directories from Trash to files due to permissions dont forget to become root:
sudo -i
then after sudo -i, go up with:
cd ..
and then
cd home/jupyter/.local/share/Trash
cd files
Best of luck,
Sadly my file was neither in the checkpoints directory, nor chromium's cache. Fortunately, I had an ext4 formatted file system and was able to recover my file using extundelete:
Figure out the drive your missing deleted file was stored on:
df /your/deleted/file/diretory/
Switch to a folder located on another you have write access to:
cd /your/alternate/location/
It is proffered to run extundlete on an unmounted partition. Thus, if your deleted file wasn't stored on the same drive as your operating system, it's recommended you unmount the partition of the deleted file (though you may want to ensure extundlete is already installed before proceeding):
sudo umount /dev/sdax
where sdax is the partition returned by your df command earlier
Use extundelete to restore your file:
sudo extundelete --restore-file /your/deleted/file/diretory/delted.file /dev/sdax
If successful your recovered file will be located at:
/your/alternate/location/your/deleted/file/diretory/delted.file
I had the very problem and I ended up solving it this way. It might be the case for some of the folks.
So I setup nginx and uwsgi using this tutorial: http://uwsgi-docs.readthedocs.org/en/latest/tutorials/Django_and_nginx.html
I finished the tutorial completely but for some reason only my images are not being loaded on the page when I run the command...
uwsgi --ini exchange_uwsgi.ini
where exchange_uwsgi.ini is my initialization file for specifying what socket I run on, wheres my project, wheres my virtualenv etc...
Just to re-iterate, the only things not showing up are my images and my images and css are all stored in one folder.
Any reason why this might happens?
Thanks
I fixed the problem.
Make sure to check the permissions on all of your static files. Only 2 images of mine were not loading and they were the only ones with incorrect permissions.
On Linux, first go to the folder with all your static files in the command window, type "ls -l" for list items with the long parameter so you can view permissions.
I set my permission on each file to -rw-rw-r--
Edit: In order to change permissions look into the command "chmod"
When I am doing cp -R at my system
cp -R \[Bark\]\ Java/ /Volumes/Seagate\ Backup\ Plus\ Drive/
its throwing this message
cp: /Volumes/Seagate Backup Plus Drive/Advanced: Read-only file system
cp: [Bark] Java//Advanced:unable to copy extended attributes to /Volumes/Seagate Backup Plus Drive/Advanced: Read-only file system.
I guess I need to make the backup disk in write mode
How to change the mode of the backup disk.
Mounting on many UNIX systems is controlled by the etc/fstab file (see here). This usually specifies mount options for each device.
You need to change the mount options for the device you're interested in.
If you examine the /etc/fstab file on your system, you should see something along the lines of ro in the options column.
If you change that to rw and then remount it, it should be writeable.
You may want to change it back when you're done so as to protect the information on it.
For Mac OSX, fstab is still used but the file systems may also be under the control of automount - look up the man pages for automount and autofs.conf for information on how to configure those.
I want to use rsync to synchronize two directories in both directions.
I refer to synchronization in classical sense
(not how it is meant in rsync manuals):
I want to update the directories in both directions,
depending on which of them is newer.
Can this be done by rsync (preferable in a Linux-way)?
If not, what other solutions exist?
Just run it twice, with "newer" mode (-u or --update flag) plus -t (to copy file modified time), -r (for recursive folders), and -v (for verbose output to see what it is doing):
rsync -rtuv /path/to/dir_a/* /path/to/dir_b
rsync -rtuv /path/to/dir_b/* /path/to/dir_a
This won't handle deletes, but I'm not sure there is a good solution to that problem with only periodic sync'ing.
Do you know Unison File Synchronizer?
Unison is a file-synchronization tool
for Unix and Windows. It allows two
replicas of a collection of files and
directories to be stored on different
hosts (or different disks on the same
host), modified separately, and then
brought up to date by propagating the
changes in each replica to the other. ...
Note also that it is resilient to failure:
Unison is resilient to failure. It is
careful to leave the replicas and its
own private structures in a sensible
state at all times, even in case of
abnormal termination or communication failures.
You need to run rsync twice and I recommend to run it with -au:
rsync -au /local/source/* /remote/destination
rsync -au /remote/destination/* /local/source
-a (a for archive) is a shortcut for -rlptgoD:
-r Recurse into sub directories
-l Also sync symbolic links
-p Also sync file permissions
-t Also sync file modification times
-g Also sync file groups
-o Also sync file owner
-D Also sync special (not regular/meta) files
Basically whenever you want to create an identical one-to-one copy using rsync, you should always use -a as that's what most users expect to happen when they talk about "syncing". Other answers here seem to overlook that sometimes the content of a file stays unchanged but its owner may have changed or its access permissions may have changed and in that case rsync would not sync the file which could be fatal.
But you also require -u as that tells rsync to completely leave any file/folder alone, in case it exists already at the destination and has a newer last modification date. Without -u rsync would sync regardless if a file/folder is newer or not.
Please note that this solution cannot handle deleted files. Handling deletes is not easily possible as consider the following situation: A file has been deleted at the source, now how shall rsync know if that file once existed and has been deleted (in that case it must be deleted at the destination as well) or whether it never existed at the source (in that case it must be copied from the destination). These two situations look identical to rsync thus it cannot know how to react correctly. It won't help to sync the other way round as that can lead to the same situation: A file exists at the source but not at the destination. Why? Has it never existed at the destination or has it been deleted? Both cases look identical to rsync.
Sync tools that can reliably sync deleted files usually manage a sync log about all past sync operations. If that log reveals that there once was a file and has been synced but now it is missing, it's clear that it has been deleted. If there never was such a file according to the log, it must be synced. By storing all log entries with timestamps, it's even possible that a deleted file comes back and gets deleted multiple times yet the sync tool will always know what to do and the result is always correct. rsync has no such log, it only relies on the current file state of two sides of the operation.
You can however build yourself a sync command using rsync and a bit POSIX shell scripting which gets already very close to a sync tool as described above. As I needed such a tool myself, here is an answer on Stackoverflow that guides you through the creation of such a script.
Thanks jsight
rsync -urv --progress dir_a dir_b && rsync -urv --progress dir_b dir_a
This would result in the second sync happening immediately after 1st sync is over. In case the directory structure is huge, this will save time, as one does not need to sit before the pc. If the structure is huge, remove the verbose and progress stuff
rsync -ur dir_a dir_b && rsync -ur dir_b dir_a
Use rsync <OPTIONS> [hostname:]source-dir [hostname:]dest-dir
for example:
rsync -pogtEtvr --progress --bwlimit=2000 xxx-files different-stuff
Will sync xxx-files to different-stuff/xxx-files .If different-stuff/xxx-files did not exist, it will create it - i.e. copy it.
-pogtEtv - just bunch of options to preserve file metadata, plus v - verbose and r - recursive
--progress - show progress of syncing in real time - super useful if you copy big files
--bwlimit=2000 - sets maximum speed of copying/syncing (bw = bandwidth)
P.S. rsync is critically important when you work over network in case of local machine you can use commands like cp.
Good Luck!
What you need is Rclone. Rclone ("rsync for cloud storage") is a command line Linux program to sync files and directories to and from different cloud storage providers (box,dropbox,ftp etc) and local filesystems. Rlone supports mirror syncing only.
Another more graphical solution which includes real-time syncing would be to use FreeFileSync, which includes the program RealTimeSync. FreefileSync support 2-way bidirectional syncing which includes handling deletes.
I was having the same question and end up using git. It might not fit your situation, but if anyone find this topic and have the same question, you may consider a version control system.
I'm using rsync with inotifywait.
When you change any file, rsync will be executed.
inotifywait -m --exclude "$_LOG_FILE" -r -e create,delete,delete_self,modify,moved_to --format "%w%f" "$folder"
You need run inotifywait on both host. Please check example inotifywait