# ELB(CLB,ALB,NLB)の種類ごとのHTTPレスポンスの違い
## ELB(CLB,ALB,NLB)の種類ごとのHTTPレスポンスの違い
ELB(CLB,ALB,NLB)の種類ごとのHTTPレスポンスの違いについて、以下のHTTPリクエストをベースにいくつかのパターンで挙動を見てみました。
```
GET / HTTP/1.1
Host: xxxxxxxxx.com
```
## echo test
HTTPリクエストをRFCに準拠しない形で送信時 ## CLB
```
$ echo test | nc clb.test.hayashier.com 80
HTTP/1.1 503 Service Unavailable.
Content-length:0
```
### ALB
```
$ echo test | nc alb.test.hayashier.com 80
HTTP/1.1 400 Bad Request
Server: awselb/2.0
Date: Mon, 29 Jan 2018 05:49:34 GMT
Content-Type: text/html
Content-Length: 138
Connection: close
400 Bad Request
400 Bad Request
```
### NLB
```
$ echo test | nc nlb.test.hayashier.com 80
HTTP/1.1 400 Bad Request
Date: Mon, 29 Jan 2018 05:49:41 GMT
Server: Apache/2.2.34 (Amazon)
Content-Length: 335
Connection: close
Content-Type: text/html; charset=iso-8859-1
400 Bad Request
Bad Request
Your browser sent a request that this server could not understand.
Apache/2.2.34 (Amazon) Server at ip-172-31-17-170.us-west-2.compute.internal Port 80
```
## GEET / HTTP/1.1\r\nHost: clb.test.hayashier.com\r\n\r
存在しないHTTPメソッド指定時 ## CLB
```
$ printf GEET / HTTP/1.1\r\nHost: clb.test.hayashier.com\r\n\r\n | nc clb.test.hayashier.com 80
HTTP/1.1 501 Method Not Implemented
Allow: GET,HEAD,POST,OPTIONS
Content-Type: text/html; charset=iso-8859-1
Date: Mon, 29 Jan 2018 06:13:44 GMT
Server: Apache/2.2.34 (Amazon)
Content-Length: 304
Connection: Close
501 Method Not Implemented
Method Not Implemented
GEET to /index.html not supported.
Apache/2.2.34 (Amazon) Server at clb.test.hayashier.com Port 80
```
### ALB
```
$ printf GEET / HTTP/1.1\r\nHost: alb.test.hayashier.com\r\n\r\n | nc alb.test.hayashier.com 80
```
### NLB
```
$ printf GEET / HTTP/1.1\r\nHost: nlb.test.hayashier.com\r\n\r\n | nc nlb.test.hayashier.com 80
HTTP/1.1 501 Method Not Implemented
Date: Mon, 29 Jan 2018 06:14:16 GMT
Server: Apache/2.2.34 (Amazon)
Allow: GET,HEAD,POST,OPTIONS
Content-Length: 304
Connection: close
Content-Type: text/html; charset=iso-8859-1
501 Method Not Implemented
Method Not Implemented
GEET to /index.html not supported.
Apache/2.2.34 (Amazon) Server at nlb.test.hayashier.com Port 80
```
## printf GEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEET / HTTP/1.1\r\nHost: clb.test.hayashier.com\r\n\r
HTTPメソッドが128文字以上のとき ## CLB
```
$ printf GEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEET / HTTP/1.1\r\nHost: clb.test.hayashier.com\r\n\r\n | nc clb.test.hayashier.com 80
HTTP/1.1 405 METHOD_NOT_ALLOWED
Content-Length: 0
Connection: Close
```
### ALB
```
$ printf GEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEET / HTTP/1.1\r\nHost: alb.test.hayashier.com\r\n\r\n | nc alb.test.hayashier.com 80
```
### NLB
```
$ printf GEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEET / HTTP/1.1\r\nHost: nlb.test.hayashier.com\r\n\r\n | nc nlb.test.hayashier.com 80
HTTP/1.1 501 Method Not Implemented
Date: Mon, 29 Jan 2018 06:15:53 GMT
Server: Apache/2.2.34 (Amazon)
Allow: GET,HEAD,POST,OPTIONS
Content-Length: 1231
Connection: close
Content-Type: text/html; charset=iso-8859-1
501 Method Not Implemented
Method Not Implemented
GEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEET to /index.html not supported.
Apache/2.2.34 (Amazon) Server at nlb.test.hayashier.com Port 80
```
## GET / HTTP/1.2\r\nHost: clb.test.hayashier.com\r\n\r
存在しないHTTPバージョン指定時 ## CLB
```
$ printf GET / HTTP/1.2\r\nHost: clb.test.hayashier.com\r\n\r\n | nc clb.test.hayashier.com 80
HTTP/1.1 200 OK
Accept-Ranges: bytes
Content-Type: text/html; charset=UTF-8
Date: Mon, 29 Jan 2018 06:17:10 GMT
ETag: 60725-2f-563c5202222f8
Last-Modified: Sat, 27 Jan 2018 17:13:02 GMT
Server: Apache/2.2.34 (Amazon)
Content-Length: 47
Connection: Close
Hello, world2!
```
### ALB
```
$ printf GET / HTTP/1.2\r\nHost: alb.test.hayashier.com\r\n\r\n | nc alb.test.hayashier.com 80
```
### NLB
```
$ printf GET / HTTP/1.2\r\nHost: nlb.test.hayashier.com\r\n\r\n | nc nlb.test.hayashier.com 80
HTTP/1.1 200 OK
Date: Mon, 29 Jan 2018 06:17:34 GMT
Server: Apache/2.2.34 (Amazon)
Last-Modified: Sat, 27 Jan 2018 15:23:55 GMT
ETag: 606ee-2f-563c399ec5b72
Accept-Ranges: bytes
Content-Length: 47
Connection: close
Content-Type: text/html; charset=UTF-8
Hello, world1!
```
## printf GET / HOGE\r\nHost: clb.test.hayashier.com\r\n\r\n | nc clb.test.hayashier.com 80
存在しないプロトコル指定時 ## CLB
```
$ printf GET / HOGE\r\nHost: clb.test.hayashier.com\r\n\r\n | nc clb.test.hayashier.com 80
HTTP/1.1 400 BAD_REQUEST
Content-Length: 0
Connection: Close
```
### ALB
```
$ printf GET / HOGE\r\nHost: alb.test.hayashier.com\r\n\r\n | nc alb.test.hayashier.com 80
HTTP/1.1 400 Bad Request
Server: awselb/2.0
Date: Mon, 29 Jan 2018 06:31:35 GMT
Content-Type: text/html
Content-Length: 138
Connection: close
400 Bad Request
400 Bad Request
```
### NLB
```
$ printf GET / HOGE\r\nHost: nlb.test.hayashier.com\r\n\r\n | nc nlb.test.hayashier.com 80
HTTP/1.1 400 Bad Request
Date: Mon, 29 Jan 2018 06:31:46 GMT
Server: Apache/2.2.34 (Amazon)
Content-Length: 335
Connection: close
Content-Type: text/html; charset=iso-8859-1
400 Bad Request
Bad Request
Your browser sent a request that this server could not understand.
Apache/2.2.34 (Amazon) Server at ip-172-31-17-170.us-west-2.compute.internal Port 80
```
## printf GET / HTTP/1.1\r\n\r\n | nc nlb.test.hayashier.com 80
HTTP/1.1でHostヘッダー未指定時 ## CLB
```
$ printf GET / HTTP/1.1\r\n\r\n | nc clb.test.hayashier.com 80
HTTP/1.1 400 BAD_REQUEST
Content-Length: 0
Connection: Close
```
### ALB
```
$ printf GET / HTTP/1.1\r\n\r\n | nc alb.test.hayashier.com 80
HTTP/1.1 400 Bad Request
Server: awselb/2.0
Date: Mon, 29 Jan 2018 12:51:06 GMT
Content-Type: text/html
Content-Length: 138
Connection: close
400 Bad Request
400 Bad Request
```
### NLB
```
$ printf GET / HTTP/1.1\r\n\r\n | nc nlb.test.hayashier.com 80
HTTP/1.1 400 Bad Request
Date: Mon, 29 Jan 2018 12:51:11 GMT
Server: Apache/2.2.34 (Amazon)
Content-Length: 335
Connection: close
Content-Type: text/html; charset=iso-8859-1
400 Bad Request
Bad Request
Your browser sent a request that this server could not understand.
Apache/2.2.34 (Amazon) Server at ip-172-31-17-170.us-west-2.compute.internal Port 80
```
## printf GET / HTTP/1.0\r\n\r\n | nc clb.test.hayashier.com 80
HTTP/1.0でHostヘッダー未指定時 ## CLB
```
$ printf GET / HTTP/1.0\r\n\r\n | nc clb.test.hayashier.com 80
HTTP/1.1 200 OK
Accept-Ranges: bytes
Content-Type: text/html; charset=UTF-8
Date: Mon, 29 Jan 2018 12:49:35 GMT
ETag: 60725-2f-563c5202222f8
Last-Modified: Sat, 27 Jan 2018 17:13:02 GMT
Server: Apache/2.2.34 (Amazon)
Content-Length: 47
Connection: Close
Hello, world2!
```
### ALB
```
$ printf GET / HTTP/1.0\r\n\r\n | nc alb.test.hayashier.com 80
```
### NLB
```
$ printf GET / HTTP/1.0\r\n\r\n | nc nlb.test.hayashier.com 80
HTTP/1.1 200 OK
Date: Mon, 29 Jan 2018 12:50:04 GMT
Server: Apache/2.2.34 (Amazon)
Last-Modified: Sat, 27 Jan 2018 17:13:02 GMT
ETag: 60725-2f-563c5202222f8
Accept-Ranges: bytes
Content-Length: 47
Connection: close
Content-Type: text/html; charset=UTF-8
Hello, world2!
```
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