Mac OS X: Time Machine Backup Slow / Stuck

Posted on by nils
1

I just noticed that my time machine backup (to a Synology NAS) was slow. As in… single-digit kilobytes per second, and then it got stuck completely. At first I thought this may be an issue with the Synology drive, but this turned out not to be true. In the log file of the Mac, I found a large number of these lines:

Sep 20 20:27:01 Ascalon.local mdworker[20883]: (Warning) Import: Bad path:

(Ascalon is the name of my Macbook Air.)

This seemed to be indicative of a filesystem error, but this was not the case.

It turned out that in my case the offending drive was an old Kindle I had connected to my Macbook to charge – it does mount as a USB drive, similar to a flash memory stick. Anyway, once unplugged the Time Machine backup ran as fast as always.

I should probably note that the Kindle itself is not defective – disk scans give it a clean bill of health. So I have to assume that something in its folder structure is not compatible with Time Machine. Unfortunately I never connected the Kindle to my Macbook Air before, so I can’t say if this is a general issue or a new bug of some sort.

Anyway, solution in this case: Unplug all USB drives one after the other, restart the Time Machine backup after each one to see which one offends, and then deal with that. You can use the disk check utility on your Mac, but please make sure you know what you are doing and do not accidentally erase it. (The Apple Knowledge Base is probably a good place to start.)

Can I safely send a Certificate Request (CSR) by Email?

Posted on by nils
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Yes. The CSR is your public key, which will be verified and signed by the certificate authority (CA) and returned to you afterward. It is this signed version you will then use in your application. It is useless without the private key, so even if someone makes a copy of it, they won’t be able to attack you.

However, this does mean that you must not send your private key out! If your private key gets stolen, the SSL certificate is compromised and must be revoked.

scrub: -X argument cannot exist

Posted on by nils
3

I’ve been looking for a utility that will clean disks for me – and I do realize this is no real substitute for shredding them. Anyway, scrub seems to do the job. However, when I tried to run it I got:

scrub: -X argument cannot exist

This had me stumped because I read it as “the -X argument cannot exist”, which seemed to make no sense whatsoever. And indeed it means “the argument to -X cannot be a directory that exists”. Simply running it with a new directory, like so:

root@server:/home# scrub -X /home/scrub
scrub: using NNSA NAP-14.x patterns
scrub: scrubbing /home/scrub/scrub.000 1073741824 bytes (~1GB)
scrub: random  |..^C                                            |

works.

It is notable that more current versions of scrub fix the error message to be more intuitive (mine was still 2.2).

Adding Blog as a Menu Item in WordPress

Posted on by nils
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On my personal blog, I set the main page to a static page. However, I also wanted a menu item to the blog posts. There was nothing in the Menu editor, but the solution is quite easy if you know how.

  1. Create and publish an empty page. I called mine “Blog”.

  2. In (Dashboard) -> Settings -> Reading, there is a drop down called “Posts page”. Select the empty page you just created. Save your changes.

  3. Under Appearance -> Menu add the Posts page to your menu. Save the menu.

When you now click on this menu item (or navigate to the page some other way) it will show the blog posts list as normal.

Apache: How To Redirect http to https

Posted on by nils
3

If you want to direct traffic from your http so that it gets encrypted, this is really easy to do in Apache:

Step one: Set up your https vhost:

<IfModule mod_ssl.c>
<VirtualHost 10.1.1.1:443>
DocumentRoot /var/www
# other server options go here as needed
# – logging for example
SSLEngine on
SSLCertificateFile /etc/ssl/certs/example.cert
SSLCertificateKeyFile /etc/ssl/private/example.key
# Add other SSL specific options as needed</pre>
</VirtualHost>
</IfModule>

Step two: Set up your http vhost:

<VirtualHost 10.1.1.1:80>
ServerName my.example.com
RedirectPermanent / https://my.example.com/
</VirtualHost>

We have previously posted more information on enabling SSL in Apache.

Obviously, instead of 10.1.1.1 and my.example.com you’ll have to use your own IP and hostname, whatever they may be.

Note that this will redirect everything from http to https. Finer control is possible, for example you could do:

RedirectPermanent /secure/ https://my.example.com/secure/

Or you could use RewriteRules for even more control. However, in the age of mass surveillance and constant threats from hackers, a general redirect to https is a good idea.

Could not perform immediate configuration on ‘python-minimal’

Posted on by nils
1

When I tried to update my Debian box, I got the following ominous error:

E: Could not perform immediate configuration on ‘python-minimal’.Please see man 5 apt.conf under APT::Immediate-Configure for details. (2)

It turns out that the fix is fairly simple. The following worked for me:

apt-get install -o APT::Immediate-Configure=false -f apt python-minimal

Creating New Outlook .PST Files in Office 2010

Posted on by nils
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Back in the good old days, I am pretty sure, all the PST related stuff was in the normal file menu. Not anymore. I wanted to create a new PST file and I had to look quite a while before I found it – Microsoft has it hidden quite well:

It’s in the Home ribbon, under “New Items -> More Items -> Outlook Data File”.

I never liked those Ribbons, but anyway, maybe this will save someone else ten minutes.

WordPress: Images not displaying, Redirects not working

Posted on by nils
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Moved my WordPress installation to a new server. I kept all paths etc intact, copied my VirtualHost and permissions were good, so I was at first surprised when my images didn’t show and redirects didn’t work. The cause was quickly found, however; it seems my old install had different default settings hidden somewhere in the Apache configuration.

I guess there may also be different causes, but in my case I fixed it by adding this to my WordPress VirtualHost:

<Directory “/var/www/wordpress/”>
Options FollowSymLinks
AllowOverride All
Order allow,deny
Allow from all
</Directory>

/var/www/wordpress is obviously the DocumentRoot of my WordPress install.

Lo and behold, my WordPress site wasn’t broken anymore.

OpenVPN Connect doesn’t work at all on iPad Air / new iPad Mini

Posted on by nils
1

Yeah this had me puzzled for a while. Basically, I configured the OpenVPN client correctly (I thought so anyway). When I attempted to connect to my server, both the in-App log window and the log of my server remained empty: From what I could tell, OpenVPN didn’t even try!

Well, it turns out that as of early December 2013, OpenVPN Connect does not work on 64bit architecture on an iPad or an iPhone. The developers expect an update in mid-2013 to fix this. So until then there is nothing that we can do about it. Too bad.

Update: Problem has been fixed in current versions of OpenVPN Connect.