[similar this question](https://unix.stackexchange.com/questions/128655/tile-logfile-into-pieces-and-search-for-errors)

i have this file

```
START1
1
2
END1
START2
error
1
2
END2
START3
1
2
END3

```

i want if `error` found; `sed` extract the whole piece and print it

for example out put is

```
START2
error
1
2
END2

```

because `error` found between `START2` and `END2`

how to solve it only with `sed` ?!?