So I built a nether portal from my house and went to the nether. When I entered back I spawned in an entirely new portal about 300 blocks from my house in an inconvenient location. How can I fix this?
This is not a glitch, it is by design.
Every time you enter a portal, Minecraft will search for a corresponding portal in the other dimension. It starts this search at an exact point based on the calculation below, and works outwards. If it finds an active portal within about 128 blocks, then it will send you there. If it finds more than one in range, it will send you to the closest one to the correct exact point.
Naturally generated portals are almost never at exactly the right point, and will need to be moved.
The calculation is done every time you enter the portal. Many players believe that a portal is 'linked' to another - this is incorrect! There is no such thing as a linked portal.
So, to get the exact point, where the destination portal should be, it is a simple calculation, based on the fact that 1 block of travel in the Nether is the same as 8 blocks of travel in the Overworld. This means you can travel great distances in the Overworld, by travelling a much shorter distance in the Nether, and using portals.
This means that to calculate the exact position to place you portal you should:
- Overworld to Nether: Divide the X and Z co-ordinates by 8 (and round to the nearest number)
- Nether to Overworld: Multiply the X and Z co-ordinates by 8.
Note that the Y co-ordinate should remain the same!
So, for example, if you have an overworld portal at -600 65 750 then your portal in the Nether should be at 75 65 94.
When you first enter a newly built portal, it may generate a new portal on the other side for you, or just throw you out of an existing one - either way, you should then move/build the portal to the correct location to ensure you always come out in the right place.
sometimes its because of positions and blocks around....i try to avoid this bug by building my portal some blocks away from my house in a big space one block above ground..for that space i burned so many trees and dig lots of dirt :)..and i also was afraid that creatures come out of portal so i put fences around it :)