The phrase "an existing connection" is correct and usable in written English.
It can be used when referring to a currently active or established link between two entities, such as devices, networks, or relationships.
Example: "Before proceeding with the update, please ensure that there is an existing connection to the server."
Alternatives: "a current connection" or "an active connection".
Reweighting is a change in the strength of an existing connection.
There is already an existing connection point in the house, but the line was taken over by the offices of the trust which owns the house and land where we live.
In addition to Langeled, another pipeline (this one from the Netherlands) is due to open later this year; an existing connection to Zeebrugge is being upgraded and a new liquefied natural gas terminal is opening at Teesside.
Apparently there was an existing connection there, since the accelerator's co-founder Zachary Aarons was an early investor in Flip.
Lately, there has been distinct evidence for an existing connection between the central nervous system and bladder voiding in preterm infants, as the voiding reflex arouses neonatal children.
Elston (who was also the vice president of product at Justin.tv) and some of his team members have an existing connection to Mixbook — they used to work at Scrapblog, which the larger company acquired.
We strengthen an existing connection-based mixed integer programming formulation involving exponentially many variables using a recent result with respect to the orientability of two-node connected graphs.
I like that you weren't afraid to reach out without any existing connections.
Based on Michael Porter's National Diamond model [8], the RTI also assumes that the technological solution is of higher significance to a country if there is a clear, existing connection to a global client base that could benefit from the new technological solution or could utilize it as an add-on to their existing products.
In the second step, the algorithm tries to remove a randomly chosen existing connection.
The four-times-weekly service provides competition for CityJet's existing connection from the Docklands airport, and an alternative to sister-airline Vueling's flights from Heathrow.
