MongoDB init.d script for Linux

If you’re thinking of trying MongoDB, one thing you’ll notice that doesn’t come with the binary downloads is an mongodb init.d script for Linux distributions, so here’s mine. It’s based on having mongodb installed in /usr/local/mongodb with the binaries in the /bin directory under there, but if you’ve got the binaries somewhere else you just need to change one line at the top of the file.

All you need to do is download the file to your Linux server, rename it from mongodb.txt to mongodb and copy it to /etc/init.d, then fix the permissions. The following commands should do it

cp mongodb.txt /etc/init.d/mongodb

chmod 755 /etc/init.d/mongodb

chown root:root /etc/init.d mongodb

Finally, you just need to run the following 2 commands to set mongodb to start on boot:

chkconfig —add mongodb

chkconfig mongodb on

The script works on Centos, but should work fine on Ubuntu, RHEL, etc with minimal changes.

Arista Network-Blog: Arista 7500 (via abnerg)

I’m glad the 7500 is finally out. It should light a fire under anyone who claims to care about ethernet performance and value. The first time I saw the specs on a roadmap, I was pretty well blown away. It looks like what they brought to market is as good. Look forward to seeing some benchmarking and test results.

(via irq)

Google offering free "Backups", nothing of the sort

There’s lots of stories floating around the web this weekend about Google offering free backups with their Google Apps product, which on the face of it seems a great additional feature for people worried about data loss.

However, even the quickest read of what Google are offering shows it’s not backup, but online replication, 2 fundamentally different solutions.

Backups protect against the following things amongst others:

  • User error – deleting or overwriting 1 or more files
  • User error – deleting or overwriting entire system including account details, etc
  • Hardware error – hardware loss causes failure/corruption of entire system
  • Hardware error – hardware loss causes deletion/corruption of 1 or more files
  • Software error – software error causes failure/corruption of entire system
  • Software error – software error causes deletion/corruption of 1 or more files

Of these 6 general events that backups protect against, Google’s new online replication service seems to protect against only 2 of them – the hardware error events.

In the event of a user deleting a file or their whole account, Google state that for every action you take “in the background we go and write that data to multiple servers within one data center and also in other data centers”, so if you delete your original file, every other “backup” copy will be deleted too. Same with over-writing it, if your file is protected using revisions in Google Docs then you’ll be ok, but that’s the same offering Google has already provided.

If you delete your account (a fairly stupid move for a user, but something a malicious administrator could do), then you are stuck again – your account deletion will not be protected by these backups.

And finally we get to software errors – we have to look at Google’s statements on the changes again, and according to them the replication is online and instant, so any system caused corruptions or deletions of files in one location will most likely be replicated in the other locations.

That’s not to say what Google is offering isn’t a great addition to the service, it really is, but with these articles you’ll end up with a bunch of mislead users who think their getting something they’re not.

Please, don’t call it a backup if you can’t do a restore!