The Bloomberg Outage: Systems Overwhelmed by Excessive Network Traffic Volume; Some Users Left in the Dark
Sell-side and buy-side firms discuss today's Bloomberg outage.

According to reports, the issues started around 3:30 a.m. ET, with services being largely restored by 6 a.m. At 11 a.m., Bloomberg tweeted that service had been fully restored to all customers.
Sources tell Inside Market Data (IMD) that the outage appears to have been global and affected many if not all of the provider's clients, though Bloomberg's other data products, such as its B-Pipe datafeed and back-office data services, were not affected by the outage.
At 5:13 a.m., Bloomberg tweeted that "there is no indication at this point that this is anything other than an internal network issue."
A Bloomberg spokesperson then told IMD that the outage was caused when software and hardware was overloaded by excessive volumes of network traffic, which overwhelmed terminals and forced them to disconnect from the network.
‘We Just Heard From Them'
The head of a Paris-based asset management firm tells WatersTechnology, "We were impacted by the outage and received a call from our normal contact at Bloomberg, who apologized and indicated that it was a server issue."
Others were yet to hear from the data-service behemoth, however.
According to a CTO at a large European futures market-making firm, all their terminals went down but they were unaware as to why. After checking their own infrastructure, they realized it was not on their side. Bloomberg support was not available, the CTO says, and they only learned from news reports that it was a global outage, the source says.
One CTO of a US-based hedge fund that deals in emerging markets tells Waters that they were down in Asia and "we could not finish our day [because] we depend on Bloomberg to enter our orders as we utilize their OIMS AIM." The CTO says that his firm was not contacted by Bloomberg until later in the day to confirm that the hedge fund's systems were back up and running.
A source at a US asset manager, meanwhile, told IMD that they were experiencing "sporadic problems with individuals reconnecting" for several hours after the UK market opened, and that Bloomberg had yet to communicate the cause of the outage.
A trader at a European bank who is based in New York says that his firm doesn't use Bloomberg apart for its research. "We were good," the trader says.
Reason for Concern
There's no doubt that this event will have a shockwave that will require firms to consider the ubiquity of Bloomberg terminals and what their back-up plans are.
One CIO of a large NY-based hedge fund tells Waters that this outage didn't affect them much as about 90 percent of their traders are based in New York, and they only have a handful in London. But the CIO expressed concern that something like this could happen at 9 a.m. ET.
"Had this been US-based, then yes, I would have had a problem."
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