Saya mencoba untuk terhubung ke server mysql jarak jauh. Ini terjadi 100% dari waktu.
client: mysql Ver 14.14 Distrib 5.7.12, untuk
server Win32 (AMD64) : 5.0.95
Ini adalah kesalahan yang saya dapatkan:
C:\>mysql -h example.com -P 3306 -D prod_rcadb -u username -p
Enter password: **********
ERROR 2027 (HY000): Malformed packet
kesalahan yang sama dengan mysqladmin:
C:\>mysqladmin -h example.com -P 3306 -u username -p version
Enter password: **********
mysqladmin: connect to server at '10.106.24.79' failed
error: 'Malformed packet'
Jadi saya mengambil pcap, hanya untuk mengetahui seperti apa percakapan itu.
Jabat tangan TCP:
1 2016-04-14 11:18:48.910690 0.000000 137.69.150.80 10.106.24.79 TCP 66 51157→3306 [SYN] Seq=0 Win=8192 Len=0 MSS=1428 WS=256 SACK_PERM=1 8192
2 2016-04-14 11:18:49.019893 0.109203 10.106.24.79 137.69.150.80 TCP 66 3306→51157 [SYN, ACK] Seq=0 Ack=1 Win=5840 Len=0 MSS=1460 SACK_PERM=1 WS=256 5840
3 2016-04-14 11:18:49.019893 0.000000 137.69.150.80 10.106.24.79 TCP 54 51157→3306 [ACK] Seq=1 Ack=1 Win=65536 Len=0 256
Negosiasi koneksi Mysql:
4 2016-04-14 11:18:49.144696 0.124803 10.106.24.79 137.69.150.80 MySQL 110 Server Greeting proto=10 version=5.0.95 23
5 2016-04-14 11:18:49.144696 0.000000 137.69.150.80 10.106.24.79 MySQL 119 Login Request user=bigdata 256<br>
6 2016-04-14 11:18:49.144696 0.000000 10.106.24.79 137.69.150.80 TCP 60 3306→51157 [ACK] Seq=57 Ack=66 Win=5888 Len=0 23
7 2016-04-14 11:18:49.316301 0.171605 10.106.24.79 137.69.150.80 MySQL 60 Response 23
Jadi klien terhubung di tingkat TCP, server menyambut kami dengan opsi dan status yang didukung:
Server Capabilities: 0xa22c
.... .... .... ...0 = Long Password: Not set
.... .... .... ..0. = Found Rows: Not set
.... .... .... .1.. = Long Column Flags: Set
.... .... .... 1... = Connect With Database: Set
.... .... ...0 .... = Don't Allow database.table.column: Not set
.... .... ..1. .... = Can use compression protocol: Set
.... .... .0.. .... = ODBC Client: Not set
.... .... 0... .... = Can Use LOAD DATA LOCAL: Not set
.... ...0 .... .... = Ignore Spaces before '(': Not set
.... ..1. .... .... = Speaks 4.1 protocol (new flag): Set
.... .0.. .... .... = Interactive Client: Not set
.... 0... .... .... = Switch to SSL after handshake: Not set
...0 .... .... .... = Ignore sigpipes: Not set
..1. .... .... .... = Knows about transactions: Set
.0.. .... .... .... = Speaks 4.1 protocol (old flag): Not set
1... .... .... .... = Can do 4.1 authentication: Set
Server Language: latin1 COLLATE latin1_swedish_ci (8)
Klien meminta login:
.... .... .... ...1 = Long Password: Set
.... .... .... ..0. = Found Rows: Not set
.... .... .... .1.. = Long Column Flags: Set
.... .... .... 0... = Connect With Database: Not set
.... .... ...0 .... = Don't Allow database.table.column: Not set
.... .... ..0. .... = Can use compression protocol: Not set
.... .... .0.. .... = ODBC Client: Not set
.... .... 1... .... = Can Use LOAD DATA LOCAL: Set
.... ...0 .... .... = Ignore Spaces before '(': Not set
.... ..1. .... .... = Speaks 4.1 protocol (new flag): Set
.... .0.. .... .... = Interactive Client: Not set
.... 0... .... .... = Switch to SSL after handshake: Not set
...0 .... .... .... = Ignore sigpipes: Not set
..1. .... .... .... = Knows about transactions: Set
.0.. .... .... .... = Speaks 4.1 protocol (old flag): Not set
1... .... .... .... = Can do 4.1 authentication: Set
Extended Client Capabilities: 0x81be
.... .... .... ...0 = Multiple statements: Not set
.... .... .... ..1. = Multiple results: Set
.... .... .... .1.. = PS Multiple results: Set
.... .... .... 1... = Plugin Auth: Set
.... .... ...1 .... = Connect attrs: Set
.... .... ..1. .... = Plugin Auth LENENC Client Data: Set
.... .... 1... .... = Session variable tracking: Set
1000 0001 .0.. .... = Unused: 0x0204
Server mengakui, lalu mengirim respons, yang pada dasarnya kosong ...
Packet Length: 1
Packet Number: 2
EOF marker: 254
Dan itu segera menyebabkan klien FIN dan menutup soket:
8 2016-04-14 11:18:49.316301 0.000000 137.69.150.80 10.106.24.79 TCP 54 51157→3306 [FIN, ACK] Seq=66 Ack=62 Win=65536 Len=0 256
9 2016-04-14 11:18:49.332901 0.016600 10.106.24.79 137.69.150.80 TCP 60 3306→51157 [ACK] Seq=62 Ack=67 Win=5888 Len=0 23
10 2016-04-14 11:18:49.391904 0.059003 10.106.24.79 137.69.150.80 TCP 60 3306→51157 [FIN, ACK] Seq=62 Ack=67 Win=5888 Len=0 23
11 2016-04-14 11:18:49.391904 0.000000 137.69.150.80 10.106.24.79 TCP 54 51157→3306 [ACK] Seq=67 Ack=63 Win=65536 Len=0 256
Jadi klien yang terhubung tidak suka paket kosong yang dikirim server.
Saya tidak mendapatkan ini terhadap server mysql lain dari versi yang sama dari klien yang sama. Berikut adalah paket respons terhadap permintaan masuk dari server 2:
Packet Length: 7
Packet Number: 2
Affected Rows: 0
Server Status: 0x0002
.... .... .... ...0 = In transaction: Not set
.... .... .... ..1. = AUTO_COMMIT: Set
.... .... .... .0.. = More results: Not set
.... .... .... 0... = Multi query - more resultsets: Not set
.... .... ...0 .... = Bad index used: Not set
.... .... ..0. .... = No index used: Not set
.... .... .0.. .... = Cursor exists: Not set
.... .... 0... .... = Last row sent: Not set
.... ...0 .... .... = database dropped: Not set
.... ..0. .... .... = No backslash escapes: Not set
.... .0.. .... .... = Session state changed: Not set
.... 0... .... .... = Query was slow: Not set
...0 .... .... .... = PS Out Params: Not set
Saya sendiri tidak mengelola db ini, tetapi jika Anda memiliki saran untuk hal-hal yang harus dicari dalam log, saya dapat meminta informasi itu.
Adakah pemikiran mengapa saya mendapatkan paket kosong kembali dari server?