More Zonkyness

We Are A Plague On The Earth

Mar 152019

Not.

I encountered this sign today at lunch when walking past a bunch of environmental protesters. I agree totally with their intentions, but this particular message is just wrong.

The earth (if sentient) is just about waking up and wondering what we are – the whole of human history and pre-history (the bits that weren’t written down) is no more than a blink in the eye of the earth. If we successfully cause an extinction-level climate change event (and so far it looks pretty successful), our entire extinction will be just another layer in the geological record – just a bit more unusual than other thin extinction layers.

The earth will quite happily get used to a warmer (or colder if it eventually settles down that way) climate equilibrium and might just (if sentient) wonder where we’ve gotten to.

The earth will go on without us; barely noticing we were here.

We’re not a plague on the earth; we’re a plague on our children.

And when you come down to it, the slogan “We Are A Plague On Our Children” is far better – it’s accurate and more personal, and harder hitting.

Foggy Itchen Bridge

Photography No Responses »

Mar 052019

Antisemites Are Jew-Haters

Politics No Responses »

Feb 262019

The most peculiar thing about antisemitism (except for the concept itself which is frankly ridiculous) is the phrase itself. The words “Semitic” is in fact today used to refer to a group of languages rather than a group of people.

And that group of languages is used by a wide collection of different people – including Arabs, Maltese, and yes, Hebrew speaking Jews.

The phrase “antisemitic” was first coined by Jew-haters to make their hatred seem more normalised and scientific. Yet, the word has been normalised and accepted by their opponents – essentially letting the Jew-haters win.

According to Jonathan M. Hess, the term was originally used by its authors to “stress the radical difference between their own ‘antisemitism’ and earlier forms of antagonism toward Jews and Judaism.”

It is not for me to dictate to anyone, but it seems to me that we should perhaps give these scum back their original names. Call a spade a spade, and a Jew-hater exactly what they are.

Manually Setting IP Addresses – Use CIDR Format!

Computing, Working Notes No Responses »

Feb 242019

Normally when you set an IP address manually on an interface you do not get a whole lot of choice of how it is done – very often you have to specify the IP address itself and a network mask. The addresses and masks are almost always specified as “dotted quads” (10.0.0.1) rather than the real address in binary or decimal (167772161).

The network mask specifies what parts of the IP address are the network address and which are the host address – to determine whether a destination needs to go via a gateway or is on the local network. This is expressed as a bitmask like 255.255.255.0. Having said that, rarely some devices (Cisco routers in the dustier parts of their code) require the reverse – 0.0.0.255.

An alternative approach is to use the CIDR format to specify both the IP address of the device and the size of the network – 10.2.9.21/24. This is used (at least) on Palo Alto Networks firewalls and is probably the simplest way of configuring a network address I have come across.

Having configured hundreds of devices with static addresses … and helped solve oodles of network configuration issues, I feel that the CIDR format method is likely to be far less error prone.

If you do need to set a netmask, use ipcalc to check what it is (and use it to cut&paste rather than risk typos) :-

✓ mike@pica» ipcalc 10.2.9.21/24 
Address:   10.2.9.21            00001010.00000010.00001001. 00010101
Netmask:   255.255.255.0 = 24   11111111.11111111.11111111. 00000000
Wildcard:  0.0.0.255            00000000.00000000.00000000. 11111111
=>
Network:   10.2.9.0/24          00001010.00000010.00001001. 00000000
HostMin:   10.2.9.1             00001010.00000010.00001001. 00000001
HostMax:   10.2.9.254           00001010.00000010.00001001. 11111110
Broadcast: 10.2.9.255           00001010.00000010.00001001. 11111111
Hosts/Net: 254                   Class A, Private Internet

Don’t Mess With My Resolv.conf

Computing, Linux, Working Notes No Responses »

Feb 092019

One of the things that irritates me about fancy new service management systems like systemd is that unless you get everything exactly right, you can end up with things interfering with specific configuration files – specifically /etc/resolv.conf.

Now as a DNS administrator, I have a certain fondness for manually controlling /etc/resolv.conf and it does actually come in useful for making temporary changes to test specific DNS servers and the like. The trouble comes when something else wants to control that file.

The ideal fix for this conflict is to have things like systemd control a separate file such as /etc/system/resolv.conf.systemd, and for /etc/resolv.conf be installed as a symbolic link pointing at the real file.

But back in the real world, if you do disable systemd-resolver which can be done with: systemctl disable systemd-resolved.service; systemctl stop systemd-resolved.service

Then you may also want to make the file immutable: chattr +i /etc/resolv.conf. On at least one server, systemd merrily re-created /etc/resolv.conf as a symbolic link to an empty file despite systemd-resolved being disabled.

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