Failed to find Build Tools revision 27.1.1. When I try to download, says it has no download link:
Referring the official documentation, the actual release is:
android {
buildToolsVersion "27.0.3"
...
}
and not 27.1.1
so, fix your android node with
android {
compileSdkVersion 27
buildToolsVersion '27.0.3'
.....
According to the Android SDK manager, the latest version of build tools are 27.0.3 and 28.0.0-rc1.
27.1.1 is the support libraries version.