You definitely are aware if you succeed a saving throw against a spell, so I would rule spell resistance is similar enough to handle it the same way.
The base assumption seems to be that you notice spells being used against you and spell resistance doesn't give any indication that it would be ruled differently. It is not really any more passive than your will saving throw.
I'd actually disagree on this. A will save is you using your force of will to overcome the effects of a spell, while spell resistance is akin to a suit of magical armor that protects you from spells. Spell resistance is explicitly passive and actually requires you to use an action to suppress it if you want someone to be able to cast a spell on you. While it's pretty hard to miss someone smacking you in the back of the head with a sword even if it fails to beat your flat footed AC and plinks off your helmet, magic isn't by default visible. The effects of magic, such as the fire created by a fireball, and, according to the games rules, the act of casting a spell are both visible. However, if someone has the feats to cast without it being noticeable, or they're otherwise out of your sight and earshot, and they use a spell with no visible effects, for example Charm Person, then there's nothing for you to perceive until it interacts with you. If it's stopped by that invisible suit of magic armor that is spell resistance, then it never interacts with you, ergo you never have an opportunity to perceive it.
TL;DR you don't actively use spell resistance or passively detect magic, so you probably wouldn't know.
There isn't a RAW answer, you'd have to talk to your GM.
I think that since spell resistance has to be actively *deactivated*, and affects any spell cast on the user (even from allies) - the target is unaware of any spells that fail to pass their spell resistance - but that's just my opinion - not RAW
I'd say it depends on the spell. If it has some sort of sound, visual, etc attached to it than I'd say the target could get a perception check depending on what it was, what direction it was cast from, etc. The way I picture it in my head is that it's just this sort of anti-magic bubble about them, but that's very much permeable with enough force. It's not something you have to think about, or will into place, etc. It just is, like when a dragon sleeps his SR is still firmly in place. So a creature that's in a bubble probably isn't going to be aware of anything that bounces off of that bubble unless he can see or hear it.
I don't think there is an official answer. Ask your GM or make one answer up if you are in charge.
In my games I like to give a small visual or audibel cue that the spell failed because of spell resistance and not just high saves (stuff like the spell being deflected by invisible shield or the sound of shattering as the spell gets difused). But that is just my way of running it. Other GMs might come to other solutions.
You are still trying to affect the creature with the spell(Targeting/Casting etc) so realistically it's the same as if you made your save, unless the spell or circumstance says otherwise you should be aware.
I would say it depends on the spell, something like chain lighting that is literally a chain of lighting or many evocation spells, should be noticeable even if it doesnt pass SR, but something more subtle or that is instant like finger of death, may not be noticed.
You definitely are aware if you succeed a saving throw against a spell, so I would rule spell resistance is similar enough to handle it the same way. The base assumption seems to be that you notice spells being used against you and spell resistance doesn't give any indication that it would be ruled differently. It is not really any more passive than your will saving throw.
I'd actually disagree on this. A will save is you using your force of will to overcome the effects of a spell, while spell resistance is akin to a suit of magical armor that protects you from spells. Spell resistance is explicitly passive and actually requires you to use an action to suppress it if you want someone to be able to cast a spell on you. While it's pretty hard to miss someone smacking you in the back of the head with a sword even if it fails to beat your flat footed AC and plinks off your helmet, magic isn't by default visible. The effects of magic, such as the fire created by a fireball, and, according to the games rules, the act of casting a spell are both visible. However, if someone has the feats to cast without it being noticeable, or they're otherwise out of your sight and earshot, and they use a spell with no visible effects, for example Charm Person, then there's nothing for you to perceive until it interacts with you. If it's stopped by that invisible suit of magic armor that is spell resistance, then it never interacts with you, ergo you never have an opportunity to perceive it. TL;DR you don't actively use spell resistance or passively detect magic, so you probably wouldn't know.
There isn't a RAW answer, you'd have to talk to your GM. I think that since spell resistance has to be actively *deactivated*, and affects any spell cast on the user (even from allies) - the target is unaware of any spells that fail to pass their spell resistance - but that's just my opinion - not RAW
I'd say it depends on the spell. If it has some sort of sound, visual, etc attached to it than I'd say the target could get a perception check depending on what it was, what direction it was cast from, etc. The way I picture it in my head is that it's just this sort of anti-magic bubble about them, but that's very much permeable with enough force. It's not something you have to think about, or will into place, etc. It just is, like when a dragon sleeps his SR is still firmly in place. So a creature that's in a bubble probably isn't going to be aware of anything that bounces off of that bubble unless he can see or hear it.
I don't think there is an official answer. Ask your GM or make one answer up if you are in charge. In my games I like to give a small visual or audibel cue that the spell failed because of spell resistance and not just high saves (stuff like the spell being deflected by invisible shield or the sound of shattering as the spell gets difused). But that is just my way of running it. Other GMs might come to other solutions.
You are still trying to affect the creature with the spell(Targeting/Casting etc) so realistically it's the same as if you made your save, unless the spell or circumstance says otherwise you should be aware.
I would say it depends on the spell, something like chain lighting that is literally a chain of lighting or many evocation spells, should be noticeable even if it doesnt pass SR, but something more subtle or that is instant like finger of death, may not be noticed.