Janar

Janar is the father or Dagna and the owner of Janar's Armorers in the east of Orzammar. Janar is part of the Smith Caste as his family has been for 100 generations,

Involvement
Janar is an armor merchant who sells various Dwarven made armors, such as Dwarven Heavy Armor and Dwarven Massive Armor. He also sells a few weapons and shields, all dwarven crafted.

If you accept the quest from Dagna to tell the Circle of Magi and then speak of this to Janar, he will tell you to try and persuade Dagna that you were wrong so she does not leave; and she should stay with her family.

Quotes
"Please, don't encourage Dagna further"