missing /etc/ directory in homebrew I am currently working on setting up an IKEv2 VPN server with strongswan. I am working on a Mac running v10.11.16 (El Capitan). I have been referencing the following tutorial: https://www.digitalocean.com/community/tutorials/how-to-set-up-an-ikev2-vpn-server-with-strongswan-on-ubuntu-16-04

I have run into issues with Step 4 of the tutorial. It seems that when I install strongswan using homebrew, the configuration files are not ending up in my etc/ folder, as they are supposed to. In fact, I can't seem to locate them anywhere on my machine. When I look in my /usr/local/opt directory, there is no etc directory included. It seems that my config files for strongswan are AWOL. Any ideas on where brew could be putting them?
If you've installed brew and strongswan to the default locations the standard "brew" etc location is /usr/local/etc/.

The folder contains all folders and sub-folders required by strongswan/ipsec etc.

Entering ls -Ral /usr/local/etc should reveal something like (slightly redacted by me to omit my user name and some unrelated folders were removed from the output):

total 40
drwxr-xr-x  12 user  admin  -  408 27 Feb 02:36 .
drwxrwxr-x  19 user  admin  -  646  7 Mär  2017 ..
-rw-r--r--   1 user  admin  -  608 27 Feb 02:36 ipsec.conf
drwxr-xr-x  10 user  admin  -  340 27 Feb 02:36 ipsec.d
-rw-------   1 user  admin  -   48 27 Feb 02:36 ipsec.secrets
drwxr-xr-x   7 user  admin  -  238 18 Dez 05:13 openssl
-rw-r--r--   1 user  admin  -  281 27 Feb 02:36 strongswan.conf
drwxr-xr-x   9 user  admin  -  306 27 Feb 02:36 strongswan.d
drwxr-xr-x  17 user  admin  -  578 27 Feb 02:36 swanctl

/usr/local/etc/ipsec.d:
total 0
drwxr-xr-x  10 user  admin  - 340 27 Feb 02:36 .
drwxr-xr-x  12 user  admin  - 408 27 Feb 02:36 ..
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 aacerts
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 acerts
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 cacerts
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 certs
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 crls
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 ocspcerts
drwxr-x---   2 user  admin  -  68 27 Feb 02:36 private
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 reqs

/usr/local/etc/ipsec.d/aacerts:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  10 user  admin  - 340 27 Feb 02:36 ..

/usr/local/etc/ipsec.d/acerts:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  10 user  admin  - 340 27 Feb 02:36 ..

/usr/local/etc/ipsec.d/cacerts:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  10 user  admin  - 340 27 Feb 02:36 ..

/usr/local/etc/ipsec.d/certs:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  10 user  admin  - 340 27 Feb 02:36 ..

/usr/local/etc/ipsec.d/crls:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  10 user  admin  - 340 27 Feb 02:36 ..

/usr/local/etc/ipsec.d/ocspcerts:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  10 user  admin  - 340 27 Feb 02:36 ..

/usr/local/etc/ipsec.d/private:
total 0
drwxr-x---   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  10 user  admin  - 340 27 Feb 02:36 ..

/usr/local/etc/ipsec.d/reqs:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  10 user  admin  - 340 27 Feb 02:36 ..

/usr/local/etc/openssl:
total 568
drwxr-xr-x   7 user  admin  -    238 18 Dez 05:13 .
drwxr-xr-x  12 user  admin  -    408 27 Feb 02:36 ..
-rw-r--r--   1 user  admin  - 275049 18 Dez 05:13 cert.pem
drwxr-xr-x   2 user  admin  -     68  6 Aug  2016 certs
drwxr-xr-x  11 user  admin  -    374 14 Nov 16:29 misc
-rw-r--r--   1 user  admin  -  10835 18 Dez 05:12 openssl.cnf
drwxr-xr-x   2 user  admin  -     68  6 Aug  2016 private

/usr/local/etc/openssl/certs:
total 0
drwxr-xr-x  2 user  admin  -  68  6 Aug  2016 .
drwxr-xr-x  7 user  admin  - 238 18 Dez 05:13 ..

/usr/local/etc/openssl/misc:
total 112
drwxr-xr-x  11 user  admin  -  374 14 Nov 16:29 .
drwxr-xr-x   7 user  admin  -  238 18 Dez 05:13 ..
-rwxr-xr-x   1 user  admin  - 5679  6 Aug  2016 CA.pl
-rwxr-xr-x   1 user  admin  - 5688 18 Dez 05:12 CA.pl.default
-rwxr-xr-x   1 user  admin  - 5175 18 Dez 05:12 CA.sh
-rwxr-xr-x   1 user  admin  -  119 18 Dez 05:12 c_hash
-rwxr-xr-x   1 user  admin  -  152 18 Dez 05:12 c_info
-rwxr-xr-x   1 user  admin  -  112 18 Dez 05:12 c_issuer
-rwxr-xr-x   1 user  admin  -  110 18 Dez 05:12 c_name
-rwxr-xr-x   1 user  admin  - 6419  5 Jun  2017 tsget
-rwxr-xr-x   1 user  admin  - 6384 18 Dez 05:12 tsget.default

/usr/local/etc/openssl/private:
total 0
drwxr-xr-x  2 user  admin  -  68  6 Aug  2016 .
drwxr-xr-x  7 user  admin  - 238 18 Dez 05:13 ..

/usr/local/etc/strongswan.d:
total 64
drwxr-xr-x   9 user  admin  -   306 27 Feb 02:36 .
drwxr-xr-x  12 user  admin  -   408 27 Feb 02:36 ..
drwxr-xr-x  29 user  admin  -   986 27 Feb 02:36 charon
-rw-r--r--   1 user  admin  -  1792 27 Feb 02:36 charon-logging.conf
-rw-r--r--   1 user  admin  - 10794 27 Feb 02:36 charon.conf
-rw-r--r--   1 user  admin  -    65 27 Feb 02:36 pki.conf
-rw-r--r--   1 user  admin  -    79 27 Feb 02:36 scepclient.conf
-rw-r--r--   1 user  admin  -   173 27 Feb 02:36 starter.conf
-rw-r--r--   1 user  admin  -   151 27 Feb 02:36 swanctl.conf

/usr/local/etc/strongswan.d/charon:
total 216
drwxr-xr-x  29 user  admin  - 986 27 Feb 02:36 .
drwxr-xr-x   9 user  admin  - 306 27 Feb 02:36 ..
-rw-r--r--   1 user  admin  - 138 27 Feb 02:36 constraints.conf
-rw-r--r--   1 user  admin  - 135 27 Feb 02:36 counters.conf
-rw-r--r--   1 user  admin  - 278 27 Feb 02:36 curl.conf
-rw-r--r--   1 user  admin  - 137 27 Feb 02:36 curve25519.conf
-rw-r--r--   1 user  admin  - 215 27 Feb 02:36 eap-gtc.conf
-rw-r--r--   1 user  admin  - 139 27 Feb 02:36 eap-identity.conf
-rw-r--r--   1 user  admin  - 134 27 Feb 02:36 eap-md5.conf
-rw-r--r--   1 user  admin  - 139 27 Feb 02:36 eap-mschapv2.conf
-rw-r--r--   1 user  admin  - 245 27 Feb 02:36 kernel-pfkey.conf
-rw-r--r--   1 user  admin  - 255 27 Feb 02:36 kernel-pfroute.conf
-rw-r--r--   1 user  admin  - 132 27 Feb 02:36 nonce.conf
-rw-r--r--   1 user  admin  - 301 27 Feb 02:36 openssl.conf
-rw-r--r--   1 user  admin  - 248 27 Feb 02:36 osx-attr.conf
-rw-r--r--   1 user  admin  - 130 27 Feb 02:36 pem.conf
-rw-r--r--   1 user  admin  - 130 27 Feb 02:36 pgp.conf
-rw-r--r--   1 user  admin  - 132 27 Feb 02:36 pkcs1.conf
-rw-r--r--   1 user  admin  - 132 27 Feb 02:36 pkcs8.conf
-rw-r--r--   1 user  admin  - 133 27 Feb 02:36 pubkey.conf
-rw-r--r--   1 user  admin  - 283 27 Feb 02:36 revocation.conf
-rw-r--r--   1 user  admin  - 491 27 Feb 02:36 socket-default.conf
-rw-r--r--   1 user  admin  - 133 27 Feb 02:36 sshkey.conf
-rw-r--r--   1 user  admin  - 986 27 Feb 02:36 stroke.conf
-rw-r--r--   1 user  admin  - 132 27 Feb 02:36 unity.conf
-rw-r--r--   1 user  admin  - 297 27 Feb 02:36 updown.conf
-rw-r--r--   1 user  admin  - 221 27 Feb 02:36 vici.conf
-rw-r--r--   1 user  admin  - 131 27 Feb 02:36 x509.conf
-rw-r--r--   1 user  admin  - 140 27 Feb 02:36 xauth-generic.conf

/usr/local/etc/swanctl:
total 32
drwxr-xr-x  17 user  admin  -   578 27 Feb 02:36 .
drwxr-xr-x  12 user  admin  -   408 27 Feb 02:36 ..
drwxr-x---   2 user  admin  -    68 27 Feb 02:36 bliss
drwxr-xr-x   2 user  admin  -    68 27 Feb 02:36 conf.d
drwxr-x---   2 user  admin  -    68 27 Feb 02:36 ecdsa
drwxr-x---   2 user  admin  -    68 27 Feb 02:36 pkcs12
drwxr-x---   2 user  admin  -    68 27 Feb 02:36 pkcs8
drwxr-x---   2 user  admin  -    68 27 Feb 02:36 private
drwxr-xr-x   2 user  admin  -    68 27 Feb 02:36 pubkey
drwxr-x---   2 user  admin  -    68 27 Feb 02:36 rsa
-rw-r-----   1 user  admin  - 14353 27 Feb 02:36 swanctl.conf
drwxr-xr-x   2 user  admin  -    68 27 Feb 02:36 x509
drwxr-xr-x   2 user  admin  -    68 27 Feb 02:36 x509aa
drwxr-xr-x   2 user  admin  -    68 27 Feb 02:36 x509ac
drwxr-xr-x   2 user  admin  -    68 27 Feb 02:36 x509ca
drwxr-xr-x   2 user  admin  -    68 27 Feb 02:36 x509crl
drwxr-xr-x   2 user  admin  -    68 27 Feb 02:36 x509ocsp

/usr/local/etc/swanctl/bliss:
total 0
drwxr-x---   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  17 user  admin  - 578 27 Feb 02:36 ..

/usr/local/etc/swanctl/conf.d:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  17 user  admin  - 578 27 Feb 02:36 ..

/usr/local/etc/swanctl/ecdsa:
total 0
drwxr-x---   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  17 user  admin  - 578 27 Feb 02:36 ..

/usr/local/etc/swanctl/pkcs12:
total 0
drwxr-x---   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  17 user  admin  - 578 27 Feb 02:36 ..

/usr/local/etc/swanctl/pkcs8:
total 0
drwxr-x---   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  17 user  admin  - 578 27 Feb 02:36 ..

/usr/local/etc/swanctl/private:
total 0
drwxr-x---   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  17 user  admin  - 578 27 Feb 02:36 ..

/usr/local/etc/swanctl/pubkey:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  17 user  admin  - 578 27 Feb 02:36 ..

/usr/local/etc/swanctl/rsa:
total 0
drwxr-x---   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  17 user  admin  - 578 27 Feb 02:36 ..

/usr/local/etc/swanctl/x509:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  17 user  admin  - 578 27 Feb 02:36 ..

/usr/local/etc/swanctl/x509aa:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  17 user  admin  - 578 27 Feb 02:36 ..

/usr/local/etc/swanctl/x509ac:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  17 user  admin  - 578 27 Feb 02:36 ..

/usr/local/etc/swanctl/x509ca:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  17 user  admin  - 578 27 Feb 02:36 ..

/usr/local/etc/swanctl/x509crl:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  17 user  admin  - 578 27 Feb 02:36 ..

/usr/local/etc/swanctl/x509ocsp:
total 0
drwxr-xr-x   2 user  admin  -  68 27 Feb 02:36 .
drwxr-xr-x  17 user  admin  - 578 27 Feb 02:36 ..