Getting rid of a Dropbox error message on a Linux-powered PC

One of my PC’s has ended up becoming a testing ground for a number of Linux distributions. The list has included openSUSE, Fedora, Arch and LMDE with Sabayon being the latest incumbent. From Arch onwards in that list though, a message has appeared on loading the desktop with every one of these when I have Dropbox’s client set up on there:

Unable to monitor entire Dropbox folder hierarchy. Please run “echo 100000 | sudo tee /proc/sys/fs/inotify/max_user_watches” and restart Dropbox to correct the problem.

Even applying the remedy that the message suggests won’t permanently fix the problem. For that, you need to edit /etc/sysctl.conf with superuser access and add the following line to it:

fs.inotify.max_user_watches = 100000

With that in place, you can issue the following command to fix the problem in the current session (assuming your user account is listed in /etc/sudoers):

sudo sysctl -p & dropbox stop & dropbox start

A reboot should demonstrate that the messages no longer appear again. For a good while, I had ignored it but curiosity eventually got me to find out how it could be stopped and led to what you find above.

Synchronising package selections between Linux Mint and Linux Mint Debian Edition

To generate the package list on the GNOME version of Linux Mint, I used the Backup Tool. It simply was a matter of using the Backup Software Selection button and telling it where to put the file that it generates. Alternatively, dpkg can be used from the command line like this:

sudo dpkg --get-selections > /backup/installed-software.txt

After transferring the file to the machine with Linux Mint Debian Edition, I tried using the Backup Tool on there too. However, using the Restore Software Selection button and loading the required only produced an irrecoverable error. Therefore, I set to looking around the web and found a command line approach that did the job for me.

The first step is to load the software selection using dpkg by issuing this command (it didn’t matter that the file wasn’t made using the dpkg command though I suspect that’s what the Linux Mint Backup Tool was doing that behind the scenes):

sudo dpkg --set-selections < /backup/installed-software.txt

Then, I started dselect and chose the installation option from the menu that appeared. First time around, it fell over but trying again was enough to complete the job. Packages available to the vanilla variant of Linux Mint but not found in the LMDE repositories were overlooked as I had hoped and installation of the extra packages had no impact on system stability either.

sudo dselect

Apparently, there is an alternative to using dselect that is based on the much used apt-get command but I didn’t make use of it so cannot say more:

sudo apt-get dselect-upgrade

All that I can say is that the dpkg/dselect combination did what I wanted so I’ll keep them in mind if ever need to synchronise software selections between two Debian-based distributions in the future again. The standard edition of Linux Mint may be based on Ubuntu rather than Debian but Ubuntu is itself based on Debian so the description holds here.

Widely differing approaches

The computer on which I am writing these words is running Linux Mint with the Cinnamon desktop environment, a fork of GNOME Shell. This looks as if it is going to be the default face of GNOME 3 in the next version of Linux Mint with the MGSE dressing up of GNOME Shell looking more and more like an interim measure until something more consistent was available. Some complained that what was delivered in version 12 of the distribution was a sort of greatest hits selection but I reckon that bets were being hedged by the project team.

Impressions of what’s coming

By default, you get a single panel at the bottom of your screen with everything you need in there. However, it is possible to change the layout so that the panel is at the top or there are two panels, one at the top and the other at the bottom. So far, there is no means of configuring which panel applet goes where as was the case in Linux Mint 11 and its predecessors. However, the default placements are very sensible so I have no cause for complaint at this point.

Just because you cannot place applets doesn’t mean that there is no configurability though. Cinnamon is extensible and you can change the way that time is displayed in the clock as well as enabling additional applets. It also is possible to control visual effects such as the way new application windows pop up on a screen.

GNOME 3 is there underneath all of this though there’s no sign of the application dashboard of GNOME Shell. The continually expanding number of slots in the workspace launcher is one sign as is the enabling of a hotspot at the top right hand corner by default. This brings up an overview screen showing what application windows are open in a workspace. The new Mint menu even gets the ability to search through installed applications together with the ability to browser through what what’s available.

In summary, Cinnamon already looks good though a little polish and extra configuration options wouldn’t go amiss. An example of the former is the placement of desktop numbers in the workspace switcher and I already have discussed the latter.¬† It does appear that the Linux Mint approach to desktop environments is taking shape with a far more conventional feel that the likes of Unity or GNOME Shell. Just as Cinnamon has become available in openSUSE, I can see it gracing LMDE too whenever Debian gets to moving over to GNOME 3 as must be inevitable now unless they take another approach such as MATE.

In comparison with revolution

While Linux Mint are choosing convention and streamlining GNOME to their own designs, it seems that Ubuntu’s Unity is getting ever more experimental as the time when Ubuntu simply evolved from one release to the next becomes an increasingly more distant memory. The latest development is the announcement that application menus could get replaced by a heads up display (HUD) instead. That would be yet another change made by what increasingly looks like a top down leadership reminiscent of what exists at Apple. While it is good to have innovation, you have to ask where users fit in all of this but Linux Mint already has gained from what has been done so far and may gain more again. Still, seeing what happens to the Ubuntu sounds like an interesting pastime though I’m not sure that I’d be depending on the default spin of this distro as my sole operating system right now. Also, changing the interface every few months wouldn’t work in a corporate environment at all so you have to wonder where Mark Shuttleworth is driving all this though Microsoft is engaging in a bit of experimentation of its own. We are living in interesting times for the computer desktop and it’s just as well that there are safe havens like Linux Mint too. Watching from afar sounds safer.

An in situ upgrade to Linux Mint 12

Though it isn’t the recommended approach, I have ended up upgrading to Linux Mint 12 from Linux Mint 11 using an in situ route. Having attempted this before with a VirtualBox hosted installation, I am well aware of the possibility of things going wrong. Then, a full re-installation was needed to remedy the situation. With that in mind, I made a number of backups in the case of an emergency fresh installation of the latest release of Linux Mint. Apache and VirtualBox configuration files together with MySQL backups were put where they could be retrieved should that be required. The same applied to the list of installed packages on my system. So far, I haven’t needed to use these but there is no point in taking too many chances.

The first step in an in-situ Linux Mint upgrade is to edit /etc/apt/sources.list. In the repository location definitions, any reference to katya (11) was changed to lisa (for 12) and the same applied to any appearance of natty (Ubuntu 11.04) which needed to become oneiric (Ubuntu 11.10). With that done, it was time to issue the following command (all one line even if it is broken here):

sudo apt-get update && sudo apt-get upgrade && sudo apt-get
dist-upgrade

Once that had completed, it was time to add the new additions that come with Linux Mint 12 to my system using a combination of apt-get, aptitude and Synaptic; the process took a few cycles. GNOME already was in place from prior experimentation¬† so there was no need to add this anew. However, I need to instate MGSE to gain the default Linux Mint customisations of GNOME 3. Along with that, I decided to add MATE, the fork of GNOME 2. That necessitated the removal of two old libraries (libgcr0 and libgpp11, if I remember correctly but it will tell you what is causing any conflict) using Synaptic. With MGSE and MATE in place, it was time to install LightDM and its Unity greeter to get the Linux Mint login screen. Using GDM wasn’t giving a very smooth visual experience and Ubuntu, the basis of Linux Mint, uses LightDM anyway. Even using the GTK greeter with LightDM produced a clunky login box in front of a garish screen. Configuration tweaks could have improved on this but it seems that using LightDM and Unity greeter is what gives the intended set up and experience.

With all of this complete, the system seemed to be running fine until the occasional desktop freeze occurred with Banshee running. Blaming that, I changed to Rhythmbox instead though that helped only marginally. While this might be blamed on how I did the upgraded my system, things seemed to have steadied themselves in the week since then. As a test, I had the music player going for a few hours and there was no problem. With the call for testing of an update to MATE a few days ago, it now looks as if there may have been bugs in the original release of Linux Mint 12. Daily updates have added new versions of MGSE and MATE so that may have something to do with the increase in stability. Even so, I haven’t discounted the possibility of needing to do a fresh installation of Linux Mint 12 just yet. However, if things continue as they are, then it won’t be needed and that’s an upheaval avoided should things go that way. That’s why in situ upgrades are attractive though rolling distros like Arch Linux (these words are being written on a system running this) and LMDE are moreso.