CONFD+ETCD Complete automatic detection of the backend server

We use the front-end forwarding here is Haproxy, using LVS or nginx can essentially change the configuration file

Create a journal file for Haproxy first

Mkdir-p/var/log/haproxy

Touch Haproxy.log

Open Rsyslog's Haproxy journaling feature to add:

$ModLoad imudp

$UDPServerRun 514

Added after #save boot message aslo to Boot.log

local0.*/var/log/haproxy/haproxy.log

Modify the/etc/sysconfig/rsyslog file to modify the syslogd_options= "" to:

Syslogd_options= "-r-m 0-c 2"

Finally, add the/etc/haproxy/haproxy.cfg file

Log 127.0.0.1 Local0

Finally, restart the Rsyslog and Haproxy services to record the diary.

Here is a complete example of Haproxy:

Global

Maxconn 51200

Chroot/var/lib/haproxy

UID 99

GID 99

Daemon

Nbproc 1

Pidfile/var/run/haproxy.pid

Log 127.0.0.1 Local0

Defaults

Mode http

Log Global

Option Httplog

Option Redispatch

Option Abortonclose

Timeout Connect 5000ms

Timeout Client 50000ms

Timeout Server 50000ms

Balance Roundrobin

Listen Admin_stats

Bind 0.0.0.0:8888

Stats Refresh 30s

Stats Uri/stats

Stats Realm Haproxy Manager

Stats auth Smecloud:[email protected]

Listen Test2

Bind 172.20.176.34:19000

Server T1 192.168.206.231:80 Check

Server T2 192.168.206.239:80 Check

Start ETCD

Etcd-name etcdserver-peer-addr 127.0.0.1:7001-addr 127.0.0.1:4001-data-dir/data/etcd-peer-bind-addr 0.0.0.0:7001- Bind-addr 0.0.0.0:4001&

Curl-l http://xxxxxxxxx:4001/v2/keys/keynames-XPUT-d value= "Sdadasdad" sets the value of the key

Curl-l Http://xxxxxxxxx:4001/v2/keys/keynames

Curl-l Http://xxxxxxxxx:4001/v2/keys/keynames-XDELETE Delete key

First create two directories/ETC/CONFD/CONF.D and/etc/confd/templates

Create a new haproxy.toml in the CONF.D directory

[Template]

Src= "Haproxy.cfg.tmpl"

Dest = "/etc/haproxy/haproxy.cfg"

Keys = [

"/app/servers",

]

Reload_cmd = "Service Haproxy Reload"

To create a new template in templates:

Global

Maxconn 51200

Chroot/var/lib/haproxy

UID 99

GID 99

Daemon

Nbproc 1

Pidfile/var/run/haproxy.pid

Log 127.0.0.1 Local0

Defaults

Mode http

Log Global

Option Httplog

Option Redispatch

Option Abortonclose

Timeout Connect 5000ms

Timeout Client 50000ms

Timeout Server 50000ms

Balance Roundrobin

Listen Admin_stats

Bind 0.0.0.0:8888

Stats Refresh 30s

Stats Uri/stats

Stats Realm Haproxy Manager

Stats auth Smecloud:[email protected]

Listen Test2

Bind 172.20.176.34:19000

{{range gets '/app/servers/* '}}

server {{base. Key}} {{. Value}} Check

{{End}}

Background start CONFD and confd-verbose-interval 10-node ' 127.0.0.1:4001 '-confdir/etc/confd >/var/log/confd.log &

At this time can etcdctl Set/app/server/dsdas Sdasdad to the ETCD fill the corresponding value when the configuration file will be automatically updated, almost real-time

Just write a script when you start the service in the back-end server and call Etcd to fill in the value API.

Comments:

1 , base
     as path. The alias of the base function that gets the last segment of the path.
{{with Get "/app/servers/prickly_blackwell"}}
    server {{base. Key}} {{. Value}} Check
{{end}}

2. Get
Returns a pair of matched kv, and returns an error if it is not found.
{{with Get '/app/servers/prickly_blackwell '}}
Key: {{. Key}}
Value: {{. Value}}
{{End}}

3, gets
Returns all matching KV and returns an error if not found.
{{range gets '/app/servers/* '}}
{{. Key}} {{. Value}}
{{End}}

4, Getv
Returns a string value that matches the key and returns an error if it is not found.
{{Getv '/app/servers/cocky_morse '}}

5, Getvs
Returns the string value of all matching keys, and returns an error if it is not found.
{{range Getvs '/app/servers/* '}}
Value: {{.}}
{{End}}

6. Split
Splits the input string by splitting the string into an array by the specified delimiter.
{{$url: = Split (Getv "/app/servers/cocky_morse") ":"}}
Host: {{index $url 0}}
Port: {{index $url 1}}

7, LS
Returns all string-type child keys that are not found and returns an error.
{{range ls '/app/servers/'}}
Subkey: {{.}}
{{End}}

8, Lsdir
Returns all the string subdirectories and returns an empty list if they are not found.
{{range lsdir '/app/'}}
SubDir: {{.}}
{{End}}

This article from "East God to a dozen five" blog, declined reprint!

CONFD+ETCD Complete automatic detection of the backend server