Installing azcopy in Gitlab Runner (Alpine Linux)
This is a glibc dependency issue on Alpine.

This azcopy binary is compatible with Linux distributions that use glibc, GNU's C standard library. Alpine Linux uses a different libc implementation, musl-libc, which is generally not compatible to glibc. When trying to run non-Alpine-built binaries on Alpine, they'll usually fail to link since the glibc shared object, libc.so.6, is missing. azcopy: not found is actually the result of the dynamic linker failing to resolve the requires libraries.

You could verify by running ldd ./azcopy:

    /lib64/ld-linux-x86-64.so.2 (0x7fa0bc9c3000)
    libpthread.so.0 =&gt; /lib64/ld-linux-x86-64.so.2 (0x7fa0bc9c3000)
    libc.so.6 =&gt; /lib64/ld-linux-x86-64.so.2 (0x7fa0bc9c3000)


Note the libc.so.6 dependency. On vanilla Alpine, there's only the musl libc binary, libc.musl-x86_64.so.1.

Fortunately, Alpine provides a light compatibility layer for glibc, through the libc6-compat package. It installs a libc.so.6 link which is redirected to the musl shared object, and adds some missing glibc interface functions. This seems to be enough to running azcopy.

Therefore, for running azcopy on Alpine, just install the libc6-compat package, using: 

apk add libc6-compat