An outage on the MTN network on Wednesday, 28 August 2013, that affected its customers as well as service providers such as Afrihost and Axxess, was confirmed to be a denial-of-service attack on MTN’s DNS cluster.
This is according to a spokesperson for Afrihost.
“The servers basically couldn’t cope with the load, and it was difficult for us to bring them up again while the attack was still in progress,” Afrihost told users on Thursday, 29 August 2013.
Afrihost explained that they diverted their domain name system (DNS) servers to Google’s Public DNS temporarily while they dealt with the problem.
“Our DNS is back up and running as of around 18:00 yesterday (28 August),” said Afrihost.
The function of DNS is to translate a web address, or uniform resource locator (URL), to an Internet Protocol (IP) address. Applications such as browsers can then use the IP address to connect to servers on the Internet.
“Some clients still seem to be using Google DNS, which will probably result in slower access than usual, and may upset some other features that are DNS reliant, particularly certain ClientZone functions,” Afrihost said.
“A quick router reboot should do the trick, but check that your DNS reverts back to our dynamic settings on 220.127.116.11. and 18.104.22.168,” the Internet service provider added.
Afrihost apologised to everyone who had connectivity problems on Wednesday.
“We really did our absolute best to get this sorted and our team were up till all hours monitoring the network to make sure we didn’t go down again,” Afrihost said.
Asked for more details about the attack, Afrihost’s Greg Payne said that denial-of-service attacks are a common problem that need to be dealt with by any ISP.
“The MTN DNS servers would normally handle this type of attack without any problems, but at the time of the attack, some changes were made to the DNS servers and there was a bug in the system that made the situation far worse than it should have been,” Payne said.
“This bug has been fixed and this issue should not happen again,” Payne said.
He said that during the outage there was great communication from MTN to Afrihost. “We hope that we in turn did a fairly good job in communicating what was going on during the outage,” Payne said.