There's no need to apologize @Hillbilly George It appears you deleted your post My comment in welcoming you wasn't intended to have this outcome... I'm terribly sorry if you feel I was "out of place" or "chastising" you for posting here or for what you posted. By all means, post when and where you will! Threads that have gone dormant for a long period of time are referred to as "zombie" threads. I hope you'll stay with us and join in some discussions.
Welcome also. I "answered" one or two "zombie threads" when I first got on here. So what..... LS was just trying to let you know that the thread wasn't active. You could have just as easily started a new topic with this question, but..... by answering that thread, it still got some answers.....
I have had a few cows that have been tethered over the years. It works for some cows, not for others. Have always had a small pen, or lot, or field, or stall, that they could be put into at night so that there were no mishaps when I wasn't available to "fix" it. But , tethering an animal can work. I found that a chain worked a little better because it didn't get tangled around their legs as easy. Used a neck chain on the cow, not a halter because that is what I had and a chain will slide around their neck so has more flexibility than a halter. The standard cow neck chain has a ring to attach it together; it is like the ring on car keys that you slide the key around until it is hanging loose. This is a "panic" ring that if the animal gets caught and panics it will actually pull apart and the animal can free its self. Works good, they have to really be struggling but it will keep them from strangling themselves.
A set of step in electric fence posts and some good electric fence wire would be more flexible and not be a huge outlay. You can put it up in any shape or configuration that you want. Permanent fencing is expensive, and electric fence and be taken down and moved or used as permanent fence and then put the cow out on a tether for a few hours at a time.
Many dairyman will use a tether system for their new calves that they put into a calf hutch. Calf gets a collar, like a dog collar, and they will use a lightweight chain or a rope. Calves like to chew on everything so ropes will get chewed on, and if they chew on a chain it won't cause any failure like a rope could over time.
I used to see cows tethered on the sides of the road all the time...free grass. Not lately tho. Too many Aholes driving up and down these back roads nowadays.