Infrastructure/Mirroring/Tiering

File:Infrastructure InfrastructureTeamN1.png

Tiering

Fedora mirror servers use Tiering, whereby a select few fast mirrors get read access to the master rsync servers, and all the other mirrors pull from those mirrors.

It turns out, 9 of our 10 Tier 0 or Tier 1 mirrors are available over Internet2. And, over half of our total mirrors are reachable over Internet2. So, let's make use of that whereever we can.

For our purposes, define:

• master: The Fedora servers dl*.fedoraproject.org
• Tier 0: The fast mirrors which pull from Red Hat's Internet2-connected master
• Tier 1: The fast mirrors which pull from the master or Tier 0 servers
• Tier 2: The mirrors that pull from the Tier 1 servers.

Properties of Tier 0 and 1 mirrors:

• Limit the number of Tier 1 mirrors to 10, to ensure adequate bandwidth for these. Adjust number up or down depending on capability of the masters.
• Must carry everything under fedora-enchilada and fedora-epel. This allows Tier 2 mirrors to exclude what they wish, but get everything if they so wish. This means at least 1TB of disk space for the Fedora portion of this server.
• Must have a 1 Gigabit connection to the Internet, or faster.
• Must have an active, available, responsive mirror administrator during the days content is staged.
• Must have at least 2 Internet2-connected Tier 1 mirrors.
• Must have at least 1 Tier 1 mirror on each continent for which we have Tier 2 mirrors
• Must serve private rsync (see below for configuration)

Master Mirrors

• dl0[12345].fedoraproject.org, in Phoenix, AZ, USA.
  • dl.fedoraproject.org is a DNS round-robin to dl[12345].
• download-i2.fedora.redhat.com in Raleigh, NC, USA (Internet2, NLR, and those reachable over NLR only)

Tier 0 Mirrors

Tier 0 mirrors can pull from Red Hat directly over the Internet2 connection.

Server	Comment	Contact for ACL
fedora-archives.ibiblio.org	Internet2 / National Lamba Rail (NLR) connected hosts.	<fedora-admin@ibiblio.org> No ACLs - open for syncing.
archive.linux.duke.edu	Internet2. Uses ACL from MirrorManager database.	Drew Stinnett <drew.stinnett at duke.edu> (spacepope on IRC)

Tier 1 Mirrors

Tier 1 mirrors pull from one of the master or Tier 0 mirrors.

Server	Comment	Contact for ACL
kernel.org	mirrors1.kernel.org, mirrors2.kernel.org - USx2, mirrors3.kernel.org - NL, mirrors4.kernel.org - SE Do not sync from mirrors.kernel.org, choose one of the ones above and use that.	<ftpadmin at kernel.org>
wpi.edu	IPv6-connected or Internet2-connected mirrors only	Chuck Anderson <cra at wpi.edu>
rsync.hrz.tu-chemnitz.de	rsync.hrz.tu-chemnitz.de::fedora-enchilada/. Uses ACL from MirrorManager database .	guenther.fischer at hrz.tu-chemnitz.de
fedora-rsync.ftp.pub.2iij.net	rsync://fedora-rsync.ftp.pub.2iij.net/fedora-enchilada	mirror-contact at iij.ad.jp
sunsite.mff.cuni.cz
ftp.heanet.ie	IPv6 and Internet2 connectivity. ftp.heanet.ie::fedora-enchilada, ftp.heanet.ie::fedora-epel	mirrors at heanet.ie
mirror.speedpartner.de	IPv4 and IPv6	mirror at speedpartner.de
fedora.c3sl.ufpr.br	South America	Carlos Carvalho carlos at fisica.ufpr.br

Tier 1 Rsync configuration

Below is an example rsyncd.conf file for a Tier 0 or Tier 1 mirror that provides private rsync access to select downstream Tier 2 mirrors. You may do this via either IP or DNS-based access control, or by a shared username/password which you give to your selected Tier 2 mirrors directly.

The key to this is that the Tier 0/1 mirror rsyncs content using a user account (e.g. mirror used below), and you serve content to Tier 2 mirrors using a private rsync module that runs as that same user account, while providing public non-authenticated rsync using the nobody account. In this way, Tier 2 mirrors may obtain content before the permissions are made world readable.

use chroot = yes
uid = nobody
gid = nobody
dont compress = *.gz *.tgz *.zip *.z *.rpm *.deb *.bz2 *.iso *.ogg *.ogv *.tbz
exclude = .snapshot/ .~tmp~/ /.private/ /.private/** **/.nfs*
ignore nonreadable = yes
list = true
read only = yes
refuse options = checksum

[ fedora-enchilada ]
        comment = Fedora - The whole enchilada
        path = /srv/pub/fedora

[ fedora-epel ]
        comment = Extra Packages for Enterprise Linux
        path = /srv/pub/epel

##
## The following are not seen and are limited by IP.
##

[fedora-enchilada0]
       comment = Fedora Enchilada for Tier0|1 Mirrors
       path = /srv/pub/fedora/
       list = no
       uid = mirror
       gid = mirror
       hosts allow = 152.46.7.122 200.17.202.1/28 zeus1.kernel.org ...

[fedora-epel0]
       comment = Fedora EPEL for Tier0|1 Mirrors
       path = /srv/pub/epel/
       list = no
       uid = mirror
       gid = mirror
       hosts allow = 152.46.7.122 200.17.202.1/28 zeus1.kernel.org ...