OSX NFS Storage Repository for XenServer

Setting up an iso Storage Repository for my XenServer testbed. CIFS is an option, but after a couple of “SR_BACKEND_FAILURE_222Could not mount the directory specified in Device Configuration” errors, I decided to try NFS, telling myself that CIFS/SMB is an ugly way of connecting unix systems to each other anyway…

OSX supports NFS nicely, and there’s a good nagware GUI available from Breslink.com.

Five minutes later my CIFS share was available over NFS.

I caught the same “SR_BACKEND_FAILURE_222…” connecting from XenServer to the NFS share until I specified “Allow mounting the folder and any subfolders inside” in the share’s advanced options – which may well be where the CIFS sharing attempt failed. XenServer presumably tries to read every subfolder of a Storage Repository as it’s mounted. I’ll test later.

Incidentally, the minimum required security was “System Standard Only”. The only other non-default sharing option was limiting access rights to the local class C subnet.

 

Planning a Citrix / XenServer installation

http://project.citrix.com/ – a hosted project planning service better than any HOWTO I’ve come across yet.

It’ll be interesting to see how well it works for a small test-bed installation.

More details (if you want a more traditional, indexed approach):

http://support.citrix.com/proddocs/topic/xendesktop/cds-library-wrapper-rho.html

 

 

Routing problem(?) between BeThere and Talktalk

I’m trying to ssh to an OpenSSHD-equipped host at {redacted}.{dynservice}.org (a TalkTalk consumer adsl account) from an nix laptop on a BeThere ADSL network.

I have no problem using ssh to connect to other servers on the internet from BeThere. *But* when I disconnect my laptop from the landline Wi-Fi and tether it through a Vodafone android phone, the laptop can ssh into the host at {redacted}.{dynservice}.org perfectly. The time-out problem only seems to arise when I’m trying to ssh from my BeThere ADSL account.

Truth table:

  • Vodafone to Bethere = ssh OK
  • Vodafone to BT = ssh OK
  • Bethere to BT = ssh FAIL

When I traceroute between the hosts, there seems to some kind of routing loop (repeated patterns of IP addresses in the traceroute).

Edit:

As of this morning, the ssh-gap (and the apparent routing loop) had cleared up. Still haven’t had a definitive answer from BeThere, but I”m happy that someone, somewhere has fixed something.

Dual boot OSX and Xen Server

Based (hopefully very closely) on an existing HOWTO.

I have an excellent general purpose i7 machine that usually works as a Hackintosh; for the sake of desk space I want it to function as a Citrix VDI testbed.

Update: As osx86 doesn’t like VT-d and Citrix definitely does, I’m using BIOS profiles with separate boot device orders.

 

 

CSS tricks with pseudo elements.

Sometimes simple jobs in restrictive frameworks make for interesting problems. Somerset Film (The Engine Room) love WordPress.com as a playground/sketchpad. Today’s problem was http://inspiresomerset.wordpress.com/ – decorated with AlienWP’s Oxygen theme but still needing a few CSS hacks to bring it up to spec – so I got involved.

When altering someone else’s css; make sparing, targeted changes and assume as little as possible – class-names are designed be re-used, so reference them uniquely by their position in the page hierarchy.  The “>” css child selector is useful here; it forces the browser’s parsing engine to ignore all but parent-child relationships, saving browser-power and time (where we still have to care about power and time).

The only unusual aspect of the job involved replacing a large image – enforced by the theme – with editable text. Setting the image’s css to display: none; hid it; but to replace it I used the before pseudo element to squeeze in extra text *before* the target class’s normal content:

#primary>#content>.recent-articles:before {
 content: "We are a new consortium of Somerset artists and producers bringing the skills and experience of professional arts and media direct to your school, children's youth centre or youth organisation. We have put together an offer we intend will be useful as well as inspirational and we look forward to hearing your feedback and ideas for taking the work forward - so do get in touch soon - subscriptions are open from March 25th.";
}

…end result:  Somerset Film are able to edit the front page text with their CSS admin form, independent of any post or page.