Can an inguinal hernia cause a lymph node to swell near the same spot? mine node near there is swollen and firm for a long time now and am concerned.

Lymph node: It could be a lymph node or a chronically incarcerated ( stuck for a long time ) hernia. Should have someone look at it.

It Should not: See a doctor. Groin hernias should not cause lymph node enlarement, generally speaking.

Monitoring Centers: Lymphatic system absorbs/carries things too big to go into the arteries/veins like bacteria eaten by white cells/digested food. Lymph nodes "taste" the lymph everywhere for bad stuff like bacteria/viruses/cancers, etc. When it detects a problem, it alerts the immune system and your body reacts. They enlarge in response to the inflammation they create when they react. They shrink when all is well.

Its possible: The node may not be a node, it may be a mass. The mass could be incarcerated contents associated with your hernia. Regardless, you need a surgery consult and a plan to repair your hernia and evaluate your node/mass.

Not usually: Not usually, but a lymph node can enlarge due to inflammation or infection.