Saturday
Jun042011

Dung Fly

A black fly which at first I thought might be a soldier fly but which turned out to be the dung fly Cordilura ciliata (Diptera: Scathophagidae).  Identified by Nikita Vikhrev here.  Note the white hairs (ciliata) on the front and middle legs!

Photo taken in the field below Chazey Wood, near Caversham, UK, on 2011-06-02.

Friday
Jun032011

Firefox ignoring /etc/hosts when DNS not available

I have a laptop running a development LAMP web server under Ubuntu 10.04 LTS.  The laptop is normally connected to a small network where the DNS name server is a modem-router with IP address 10.0.0.2.  The relevant parts of the network configuration files are as follows:

 /etc/resolv.conf:
nameserver 10.0.0.2
...

/etc/hosts:
127.0.0.1 localhost laptop site.laptop
...

/etc/nsswitch.conf:
...
hosts files mdns4_minimal [NOTFOUND=return] dns mdns4
...

/etc/host.conf:
order hosts, bind
...

This all works as expected if the laptop is connected to the network and the DNS name server is available:  I can ping site.laptop and can also visit the site.laptop website in Firefox 3.6.17.  However, when I disconnect the laptop from the network and the DNS server is no longer available I can still ping site.laptop but in Firefox I get "Server not found" whenever I try to visit site.laptop.

I tried all sorts of things in my attempts to fix this problem, and learned a lot about DNS in the process, but nothing worked.  And then I remembered that a while back I had disabled IPv6 DNS in Firefox to fix a bug which was delaying page loads.  I reasoned that the bug that caused the delay might well have been fixed by now, so I entered about:config in the Firefox URL bar and then set network.dns.disableIPv6 back to its default value of false.

This fixed my "Server not found" problem: I can now get to site.laptop in Firefox with or without the DNS name server available; and the slow page load problem has not returned.

Friday
Jun032011

Moth

A Mother Shipton moth, Callistege mi (Lepidoptera: Noctuidae), so-called because the wing pattern looks like a profile of the Yorkshire 'witch' Mother Shipton.

Photos taken in the field below Chazey Wood, near Caversham, UK, on 2011-05-04.

Thursday
Jun022011

Tachinid Flies

More tiny Tachinids, this time probably Phasia pusilla (Diptera: Tachinidae), also on knapweed (Centaurea sp).  The larvae of this species parasitize various heteropteran bugs, several species of which are common in the long grass here.

Photos taken in Whiteknights Park, Reading University grounds, Reading, UK, on 2011-05-30.

Wednesday
Jun012011

Tachinid Fly

A tiny tachinid: probably Phasia obesa (Diptera: Tachinidae) on knapweed (Centaurea sp).  The larvae are parasites of various hemipteran bugs, including Leptopterna dolabrata which is common  in the long grass here.

Photos taken in Whiteknights Park, Reading University grounds, Reading, UK, on 2011-05-30.