Many Internet users have expressed gratitude towards the Tertiary Education Network’s Mirror.ac.za service making a variety of up-to-date content available to consumers locally.<\/p>\n
Some of the content includes various Linux distributions, MIT Open Courseware and software such as MySQL and PHP.<\/p>\n
“As an open source developer I would just like to express my heartfelt appreciation of TENET, and their http:\/\/mirror.ac.za<\/a> archives. Your speeds rock, your archives are up to date,” said well known IT expert, Roelf Diedericks.<\/p>\n Mirror.ac.za details<\/strong><\/p>\n Mirror.ac.za is currently an any-casted service, made up of two machines (with an option to pull two more in, one at each cluster point as explained below) during release times.<\/p>\n The service in normal operating mode has one server in Cape Town and one server in Johannesburg. Using DNS anycasting, a client will get redirected to the server that is closest to them in terms of logical network routing. <\/p>\n Each server is a Quad Dual-Core Xeon system with 24GB of memory. In Cape Town, there is approximately 18 terabytes of disk space, while in Johannesburg there is approximately 21 terabytes of disk space. <\/p>\n The Cape Town server is linked via two 1Gbps network connections into the TENET backbone. In Cape Town there is 10Gbps of national peering with Internet Solutions as well as some national transit bandwidth. <\/p>\n “The Johannesburg server is linked directly into the TENET backbone with a 10Gbps network connection, and from there we have 10Gbps of national peering with Internet Solutions, some national transit bandwidth and a 1 gigabit connection into the JINX peering exchange,” said TENET’s Andrew Alston.<\/p>\n “It should be noted that clients behind our JINX peers will always get redirected to the Johannesburg server irrespective of physical location, unless we also peer with them in Cape Town.”<\/p>\n Lots of traffic<\/strong><\/p>\n “The Mirror.ac.za servers also have access to approximately 280Mbps of outbound international capacity. For international clients, we load balance the servers equally, again using an anycast method to do this.”<\/p>\n Alston points out that on average the combined service pushes anywhere from 50Mbps to 100Mbps, dependent on the time of day and week.<\/p>\n “During release periods, however, the servers have peaked at over 400Mbps with our total data output in a single 24-hour period peaking at approximately 2.8 terabytes during the last Ubuntu release,” said Alston.<\/p>\n Mirror.ac.za hosts most of the major open source distributions, and is the official home to za.releases.ubuntu.com, za.archive.ubuntu.com and ftp.za.freebsd.org<\/a>. <\/p>\n “We also host mirrors of commonly used open source applications such as MySQL and OpenOffice.org. On the academic side, some of the biggest data on the servers consists of academic data sets – the international bio-informatics mirror would be one such example – as well as academic open source distributions such as scientific Linux,” Alston says.<\/p>\n