ifquery: could not parse /etc/network/interfaces (Apache and proftpd)

When starting Apache I get this message:
```
:~# rc-service apache2 start
grep: /proc/filesystems: No such file or directory
* Checking local filesystems ... [ ok ]
grep: /proc/filesystems: No such file or directory
grep: /proc/filesystems: No such file or directory
* Remounting filesystems ... [ ok ]
grep: /proc/filesystems: No such file or directory
grep: /proc/filesystems: No such file or directory
* Mounting local filesystems ... [ ok ]
grep: /proc/filesystems: No such file or directory
grep: /proc/filesystems: No such file or directory
* Starting networking ...
ifquery: could not parse /etc/network/interfaces
* ERROR: networking failed to start
* ERROR: cannot start apache2 as networking would not start
```
The same occurs when I start `proftpd` while `sshd` runs normally:
```
~# rc-service proftpd start
grep: /proc/filesystems: No such file or directory
* Starting networking ...
ifquery: could not parse /etc/network/interfaces
* ERROR: networking failed to start
* ERROR: cannot start proftpd as networking would not start
```
It appears that a file is missing, but when I look at my Ubuntu in `/etc/networks`, then this file is missing as well, but Apache does not complain about this.

I tried starting networkmanager:
```
~# rc-service networkmanager start
* rc-service: service `networkmanager' does not exist
```
Then I installed it `apk add networkmanager` but to no avail. Same issue.

Start by reproducing the failure with rc-service apache2 start or rc-service proftpd start and inspect /etc/network/interfaces alongside the ifquery error. Compare the expected interface configuration with what ifquery can parse; done means networking starts without the parse error and the affected services can start.

Written by the indexing model from the issue text.