Holders Birmingham Bears will face Essex in the quarter-finals of the T20 Blast after rain washed out all but two of the last round of group matches.
Essex progressed to the last eight after Glamorgan lost to Gloucestershire in a match reduced to five overs each.
In the other ties, North Group runners-up Worcestershire face Hampshire, Sussex play Northants and South Group winners Kent will host Lancashire.
The matches will take place between 12 and 15 August.
|T20 Blast quarter-finals 2015|
|Sussex v Northants (Hove) - 12 August, 18:30 BST|
|Birmingham v Essex (Edgbaston) - 13 August, 18:30 BST|
|Worcestershire v Hampshire (Worcester) - 14 August, 17:30 BST|
|Kent v Lancashire (Canterbury) - 15 August, 14:30 BST|
|*All matches have one reserve day in the event of adverse weather|
A raft of abandonments meant the four teams to qualify from the North group were decided early in the evening.
Nottinghamshire briefly went into the top four in the North Group after their game at Leicester was called off, but the decision to abandon Lancashire's match against Worcestershire moments later meant they were eliminated on net run-rate.
"It's unfortunate for Notts, but of course good news for us," said Lancashire coach Ashley Giles.
"It's not the way you want to go through to a quarter-final but one of our targets was to get to the quarters for a start, then move on from there."
Essex were forced to wait on the result in Cardiff after their match at home against Kent was the last to be abandoned.
But Gloucestershire's win meant the Eagles progressed as the fourth-placed team in the South Group thanks to the point they gained from the no-result at Chelmsford.
"It's been a tense night," said Essex captain Ryan ten Doeschate.
"We would have liked to have played and done the job ourselves, but in the end we've got there.
"I feel over the length of the campaign we deserve to be in the last eight and given our start, [four defeats from the first five games] we would have taken fourth spot."
Essex's meeting with Birmingham will be a repeat of last season's quarter-final at Chelmsford, which the Bears won by 19 runs.