[CentOS-mirror] Proposal for a mirror hierarchy

Thu Dec 10 03:17:16 UTC 2009
Shaun Ewing <s.ewing at aussiehq.com.au>

On 9/12/09 9:53 PM, "Karanbir Singh" <mail-lists at karan.org> wrote:

> Thats good to know. There are a few fairly well connected mirrors in
> Europe and the US as well. The black holes, from my perspective, are
> Austalia/NZ, almost all of Africa and South America.

KB,

Mind if I ask how you come to the conclusion that there's a mirror black
hole in Australia?

I believe that the Australian mirror structure is quite good. As an example,
on a population to mirror ratio we have nearly double what the US has.

Of the 11 public mirrors we have, the majority of the eyeballs within
Australia have either direct access with a mirror on their network (eg:
Telstra and Optus have mirrors) or have access to another network via
peering.

The academic community is also well served by AARNet's mirror as well as
those offered by various universities such as Monash and Swinburne.

Our mirror doesn't have near as much capacity as AARNet's mirror for
example, but I'm yet to see it approach anywhere near the capacity that
we've given it (our OpenOffice.org mirror for example easily does 10-20x the
traffic of our CentOS mirror). If this holds true across the entire
Australian mirror network, then we're anything but a black hole.

About 30% of the Australian mirrors are also IPv6 connected - three of the
public mirrors have IPv6 support on their main hostname including ours and I
know of one other that has IPv6 support via an alternate hostname.

DVDs are of course lacking but I don't believe this is due to a lack of
interest from mirrors themselves but merely a lack of a procedure/capacity
to get that content out to mirrors.  We've always carried DVDs of the latest
releases (we'll BT them + seed for 72 hours and then stick them in the
mirror structure manually after verifying MD5/SHA1) but I've just had DVDs
added across the board (using AARNet's mirror - Alex, if you have any
objections please let me know).

New Zealand seems to be a different story with only one mirror over there. I
do however know that it's less than 30ms across the Tasman, and we do have a
number of downloads from NZ based hosts (about 5% compared to our Australian
based traffic using DNS based identification only - not GeoIP).

Just some thoughts...

-Shaun

-- 
Shaun Ewing
Chief Technology Officer
AussieHQ Pty Ltd

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