-
Notifications
You must be signed in to change notification settings - Fork 0
/
redis-sentinelmo-shi.html
362 lines (308 loc) · 25 KB
/
redis-sentinelmo-shi.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="author" content="CatsAction" />
<meta property="og:type" content="article" />
<meta name="twitter:card" content="summary">
<meta name="keywords" content="Redis, Redis, " />
<meta property="og:title" content="Redis Sentinel模式"/>
<meta property="og:url" content="./redis-sentinelmo-shi.html" />
<meta property="og:description" content="文章最后，我会基于Docker部署Redis主从和验证Sentinel模式。相关实现已经放到我的GitHub博客源，欢迎克隆交流学习。Docker搭建Redis主从和Sentinel Redis主从同步原理 1，增量同步 主从服务器同步的是执行的指令流。当主服务器收到指令时，会将指令写到buffer（buffer大小固定，可配置更改），然后异步将执行指令同步到从服务器。 当buffer空间不足时，新收到指令会导致旧数据覆盖，这时会触发快照同步。 2，快照同步 Redis主服务会生成快照文件dump.rdb，当从服务首次连接到主服务器上或主服务重启时，主服务将dump.rdb文件传送给从服务器，从服务清空旧数据，然后利用dump.rdb文件 恢复最新的数据，恢复完成后，再和主服务器行增量同步保持数据一致。 3，主从同步流程 （1）从服务根据配置的ip和port连接到主服务，如何主服务设置口令需要提供相应口令。 （2）从服务和主服务成功匹配后，先进行一次快照同步。 （3）快照同步完成后，主从服务进行增量同步。从服务会维护一个数据offset，并与主服务保持同步。 （4）主从服务会按一定频率给对方发送heartbeat，用于检测对方是不是正常在线。如果网络断开然后恢复，会自动重连，并通过offset判断是否需要快照同步。 （5 …" />
<meta property="og:site_name" content="CatsAction's blog" />
<meta property="og:article:author" content="CatsAction" />
<meta property="og:article:published_time" content="2020-01-09T00:00:00+08:00" />
<meta name="twitter:title" content="Redis Sentinel模式">
<meta name="twitter:description" content="文章最后，我会基于Docker部署Redis主从和验证Sentinel模式。相关实现已经放到我的GitHub博客源，欢迎克隆交流学习。Docker搭建Redis主从和Sentinel Redis主从同步原理 1，增量同步 主从服务器同步的是执行的指令流。当主服务器收到指令时，会将指令写到buffer（buffer大小固定，可配置更改），然后异步将执行指令同步到从服务器。 当buffer空间不足时，新收到指令会导致旧数据覆盖，这时会触发快照同步。 2，快照同步 Redis主服务会生成快照文件dump.rdb，当从服务首次连接到主服务器上或主服务重启时，主服务将dump.rdb文件传送给从服务器，从服务清空旧数据，然后利用dump.rdb文件 恢复最新的数据，恢复完成后，再和主服务器行增量同步保持数据一致。 3，主从同步流程 （1）从服务根据配置的ip和port连接到主服务，如何主服务设置口令需要提供相应口令。 （2）从服务和主服务成功匹配后，先进行一次快照同步。 （3）快照同步完成后，主从服务进行增量同步。从服务会维护一个数据offset，并与主服务保持同步。 （4）主从服务会按一定频率给对方发送heartbeat，用于检测对方是不是正常在线。如果网络断开然后恢复，会自动重连，并通过offset判断是否需要快照同步。 （5 …">
<title>Redis Sentinel模式 ·
CatsAction's blog
</title>
<link href="//netdna.bootstrapcdn.com/twitter-bootstrap/2.3.2/css/bootstrap-combined.min.css" rel="stylesheet">
<link rel="icon" type="image/x-icon" href="./theme/image/logo.ico" />
<link rel="stylesheet" type="text/css" href="./theme/css/elegant.prod.css" media="screen">
<link rel="stylesheet" type="text/css" href="./theme/css/custom.css" media="screen">
</head>
<body>
<div id="content">
<div class="navbar navbar-static-top">
<div class="navbar-inner">
<div class="container-fluid">
<a class="btn btn-navbar" data-toggle="collapse" data-target=".nav-collapse">
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</a>
<a class="brand" href="./"><span class=site-name>CatsAction's blog</span></a>
<div class="nav-collapse collapse">
<ul class="nav pull-right top-menu">
<li >
<a href=
.
>Home</a>
</li>
<li ><a href="./categories.html">Categories</a></li>
<li ><a href="./tags.html">Tags</a></li>
<li ><a href="./archives.html">Archives</a></li>
<li><form class="navbar-search" action="./search.html" onsubmit="return validateForm(this.elements['q'].value);"> <input type="text" class="search-query" placeholder="Search" name="q" id="tipue_search_input"></form></li>
</ul>
</div>
</div>
</div>
</div>
<div class="container-fluid">
<div class="row-fluid">
<div class="span1"></div>
<div class="span10">
<article itemscope>
<div class="row-fluid">
<header class="page-header span10 offset2">
<h1>
<a href="./redis-sentinelmo-shi.html">
Redis Sentinel模式
</a>
</h1>
</header>
</div>
<div class="row-fluid">
<div class="span8 offset2 article-content">
<p>文章最后，我会基于Docker部署Redis主从和验证Sentinel模式。相关实现已经放到我的GitHub博客源，欢迎克隆交流学习。<a href="https://github.com/boyaziqi/CatsAction/tree/master/examples/redis-replication">Docker搭建Redis主从和Sentinel</a></p>
<h2>Redis主从同步原理</h2>
<h6>1，增量同步</h6>
<p>主从服务器同步的是执行的指令流。当主服务器收到指令时，会将指令写到buffer（buffer大小固定，可配置更改），然后异步将执行指令同步到从服务器。
当buffer空间不足时，新收到指令会导致旧数据覆盖，这时会触发快照同步。</p>
<h6>2，快照同步</h6>
<p>Redis主服务会生成快照文件dump.rdb，当从服务首次连接到主服务器上或主服务重启时，主服务将dump.rdb文件传送给从服务器，从服务清空旧数据，然后利用dump.rdb文件
恢复最新的数据，恢复完成后，再和主服务器行增量同步保持数据一致。</p>
<h6>3，主从同步流程</h6>
<p>（1）从服务根据配置的ip和port连接到主服务，如何主服务设置口令需要提供相应口令。</p>
<p>（2）从服务和主服务成功匹配后，先进行一次快照同步。</p>
<p>（3）快照同步完成后，主从服务进行增量同步。从服务会维护一个数据offset，并与主服务保持同步。</p>
<p>（4）主从服务会按一定频率给对方发送heartbeat，用于检测对方是不是正常在线。如果网络断开然后恢复，会自动重连，并通过offset判断是否需要快照同步。</p>
<p>（5）从服务不处理过期key。当某个key过期时，主服务会模拟一个DEL指令发送给从服务器。</p>
<p><center>
<img alt="dockers_vm" src="./images/redis_master_replication.jpg">
</center></p>
<h2>Sentinel模式简介</h2>
<p>Redis主从服务采取读写分离，主服务负责写，从服务负责读。当主服务宕机时，Redis主从并不会从新选择主服务，这将导致整个主从服务无法正常工作。官方推荐的
主从同步高可用方案是Sentinel，它会监控和复制服务状态，当主服务宕机后，会根据选举算法从后端从服务选择新的主服务。Sentinel本身也有单点瓶颈的问题，因此也需要集群。</p>
<p><center>
<img alt="dockers_vm" src="./images/redis_sentinel.jpg">
</center></p>
<h2>工作机制</h2>
<p>Sentinel会运行三个定时任务（监控，通知，故障迁移）。当Redis主服务宕机后，会根据一定的机制选择一个领导Sentinel来执行故障迁移。主服务选择出来并配置成功后，领导Sentinel
通过<code>slaveof ip port</code>让其他从服务同步新的主服务。原来的主服务如果重新加入，则会成为新主服务的从服务。</p>
<h6>如何确认一个服务已经故障</h6>
<p>当一个Sentinel ping不通一个服务节点时，并不会立即认为该服务节点故障（主观下线）。只有当所有Sentinel协商一致，才认为该服务节点故障（客观下线）。</p>
<h6>领导选举机制</h6>
<ul>
<li>每个做出主观下线的Sentinel将向其它Sentinel发送命令，要求将自己设为领导Sentinel。</li>
<li>收到命令的Sentinel如果没有同意过其它Sentinel的领导请求命令，那就同意，否则拒绝。</li>
<li>如果该Sentinel发现自己票数超过Sentinel集合的一半且达到quorum，该Sentinel将成为领导Sentinel。</li>
<li>如果此过程有多个Sentinel成为领导Sentinel，那么将等待一段时间重新进行选举。</li>
</ul>
<h6>从服务节点选择机制</h6>
<ul>
<li>选择slave-priority（slave优先级）最高的slave节点，如果有返回，没有继续。</li>
<li>选择复制偏移量最大的slave节点（复制最完整），如果有返回，没有继续。</li>
<li>选择runId最小的slave节点。</li>
</ul>
<h2>测试</h2>
<p>为了方便验证和部署Redis主从，我基于Docker-compose构建了验证环境，实现查看文章开头的信息。docker-compose.yml文件内容如下。
其中RedisA作为主服务节点，RedisB和RedisC作为从服务节点。</p>
<div class="highlight"><pre><span></span><span class="nt">version</span><span class="p">:</span> <span class="s">'3'</span>
<span class="nt">services</span><span class="p">:</span>
<span class="nt">redisA</span><span class="p">:</span>
<span class="nt">image</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">redis</span>
<span class="nt">restart</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">always</span>
<span class="nt">ports</span><span class="p">:</span>
<span class="p p-Indicator">-</span> <span class="s">"6376:6379"</span>
<span class="nt">volumes</span><span class="p">:</span>
<span class="p p-Indicator">-</span> <span class="l l-Scalar l-Scalar-Plain">./config/redis1/:/usr/local/etc/redis/</span>
<span class="p p-Indicator">-</span> <span class="l l-Scalar l-Scalar-Plain">./logs/redis1/:/var/log/redis/</span>
<span class="nt">command</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">redis-server /usr/local/etc/redis/redis.conf</span>
<span class="nt">redisB</span><span class="p">:</span>
<span class="nt">image</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">redis</span>
<span class="nt">restart</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">always</span>
<span class="nt">ports</span><span class="p">:</span>
<span class="p p-Indicator">-</span> <span class="s">"6377:6379"</span>
<span class="nt">volumes</span><span class="p">:</span>
<span class="p p-Indicator">-</span> <span class="l l-Scalar l-Scalar-Plain">./config/redis2/:/usr/local/etc/redis/</span>
<span class="p p-Indicator">-</span> <span class="l l-Scalar l-Scalar-Plain">./logs/redis2/:/var/log/redis/</span>
<span class="nt">command</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">redis-server /usr/local/etc/redis/redis.conf</span>
<span class="nt">redisC</span><span class="p">:</span>
<span class="nt">image</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">redis</span>
<span class="nt">restart</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">always</span>
<span class="nt">ports</span><span class="p">:</span>
<span class="p p-Indicator">-</span> <span class="s">"6378:6379"</span>
<span class="nt">volumes</span><span class="p">:</span>
<span class="p p-Indicator">-</span> <span class="l l-Scalar l-Scalar-Plain">./config/redis3/:/usr/local/etc/redis/</span>
<span class="p p-Indicator">-</span> <span class="l l-Scalar l-Scalar-Plain">./logs/redis3/:/var/log/redis/</span>
<span class="nt">command</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">redis-server /usr/local/etc/redis/redis.conf</span>
<span class="nt">sentinelA</span><span class="p">:</span>
<span class="nt">image</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">redis</span>
<span class="nt">restart</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">always</span>
<span class="nt">ports</span><span class="p">:</span>
<span class="p p-Indicator">-</span> <span class="s">"6381:6379"</span>
<span class="nt">volumes</span><span class="p">:</span>
<span class="p p-Indicator">-</span> <span class="l l-Scalar l-Scalar-Plain">./config/sentinel/:/usr/local/etc/redis/</span>
<span class="p p-Indicator">-</span> <span class="l l-Scalar l-Scalar-Plain">./logs/sentinel1/:/var/log/redis/</span>
<span class="nt">command</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">redis-sentinel /usr/local/etc/redis/sentinel.conf</span>
<span class="nt">sentinelB</span><span class="p">:</span>
<span class="nt">image</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">redis</span>
<span class="nt">restart</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">always</span>
<span class="nt">ports</span><span class="p">:</span>
<span class="p p-Indicator">-</span> <span class="s">"6382:6379"</span>
<span class="nt">volumes</span><span class="p">:</span>
<span class="p p-Indicator">-</span> <span class="l l-Scalar l-Scalar-Plain">./config/sentinel/:/usr/local/etc/redis/</span>
<span class="p p-Indicator">-</span> <span class="l l-Scalar l-Scalar-Plain">./logs/sentinel2/:/var/log/redis/</span>
<span class="nt">command</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">redis-sentinel /usr/local/etc/redis/sentinel.conf</span>
<span class="nt">sentinelC</span><span class="p">:</span>
<span class="nt">image</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">redis</span>
<span class="nt">restart</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">always</span>
<span class="nt">ports</span><span class="p">:</span>
<span class="p p-Indicator">-</span> <span class="s">"6383:6379"</span>
<span class="nt">volumes</span><span class="p">:</span>
<span class="p p-Indicator">-</span> <span class="l l-Scalar l-Scalar-Plain">./config/sentinel/:/usr/local/etc/redis/</span>
<span class="p p-Indicator">-</span> <span class="l l-Scalar l-Scalar-Plain">./logs/sentinel3/:/var/log/redis/</span>
<span class="nt">command</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">redis-sentinel /usr/local/etc/redis/sentinel.conf</span>
</pre></div>
<p>修改RedisB的配置文件<code>./config/redis2/redis.conf</code>，加入如下配置指定主服务节点地址。RedisC配置相同。</p>
<div class="highlight"><pre><span></span>slaveof redis-replication_redisA_1 <span class="m">6379</span>
</pre></div>
<p>增加上面的配置后，在终端docker-compose.yml文件所在目录执行<code>docker-compose up</code>启动容器，这样一主两从的Redis主从服务就搭建好了。 可以在主服务节点set一个key验证从服务节点是否正常复制。</p>
<p>我们在终端执行命令<code>docker ps</code>查看容器运行情况，我机器上显示如下，每个人的CONTAINER ID不一样。</p>
<div class="highlight"><pre><span></span>CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
ce0c4d42c6a0 redis <span class="s2">"docker-entrypoint.s…"</span> About a minute ago Up About a minute <span class="m">0</span>.0.0.0:6376->6379/tcp redis-replication_redisA_1
d21706b6ee24 redis <span class="s2">"docker-entrypoint.s…"</span> About a minute ago Up About a minute <span class="m">0</span>.0.0.0:6378->6379/tcp redis-replication_redisC_1
b515bb2db9b5 redis <span class="s2">"docker-entrypoint.s…"</span> About a minute ago Up About a minute <span class="m">0</span>.0.0.0:6377->6379/tcp redis-replication_redisB_1
bb546bd4834c redis <span class="s2">"docker-entrypoint.s…"</span> About a minute ago Up About a minute <span class="m">0</span>.0.0.0:6382->6379/tcp redis-replication_sentinelB_1
297d8af73a96 redis <span class="s2">"docker-entrypoint.s…"</span> About a minute ago Up About a minute <span class="m">0</span>.0.0.0:6383->6379/tcp redis-replication_sentinelC_1
86883db74e7d redis <span class="s2">"docker-entrypoint.s…"</span> About a minute ago Up About a minute <span class="m">0</span>.0.0.0:6381->6379/tcp redis-replication_sentinelA_1
</pre></div>
<p>在Sentinel配置文件<code>.config/sentinel/sentinel.conf</code>加入下面配置。</p>
<div class="highlight"><pre><span></span>protected-mode no
sentinel monitor redis-replication_redisA_1 <span class="m">192</span>.168.11.128 <span class="m">6379</span> <span class="m">2</span>
</pre></div>
<p>重新启动容器，这时Sentinel服务会自动更新配置文件，增加一些必要配置信息，并且将主机名和端口用一个hash字符串表示。</p>
<p>执行下面命令停止主服务节点。</p>
<div class="highlight"><pre><span></span>docker stop redis-replication_redisA_1
</pre></div>
<p>执行了上面的命令后，我们验证，RedisB已经成为新的主服务节点。如果尝试在RedisC写入，则会提示下面错误。</p>
<div class="highlight"><pre><span></span><span class="o">(</span>error<span class="o">)</span> READONLY You can<span class="err">'</span>t write against a <span class="nb">read</span> only replica.
</pre></div>
<p>执行下面的命令重启RedisA，可以看到现在它成为RedisB的从服务器。</p>
<div class="highlight"><pre><span></span>docker restart redis-replication_redisA_1
</pre></div>
<p>ps: 如果客户端与旧主服务器分隔在一起，写入的数据在恢复后由于旧主会复制新主的数据会造成数据丢失。</p>
<hr />
<aside>
<nav>
<ul class="articles-timeline">
<li class="previous-article">« <a href="./redisxi-lie-yi.html"
title="Previous: Redis系列一 - 概念和数据类型">Redis系列一 <small class="subtitle">概念和数据类型</small></a></li>
</ul>
</nav>
</aside>
</div>
<section id="article-sidebar" class="span2">
<h4>Published</h4>
<time itemprop="dateCreated" datetime="2020-01-09T00:00:00+08:00"> 1
9, 2020</time>
<!---->
<h4>Category</h4>
<a class="category-link"
href="./categories.html#redis-ref">Redis</a>
<h4>Tags</h4>
<ul class="list-of-tags tags-in-article">
<li><a href="./tags.html#redis-ref">Redis
<span>5</span>
</a></li>
</ul>
<h4>Stay in Touch</h4>
<div id="sidebar-social-link">
<a href="mailto:[email protected]" title="My Email Address" target="_blank" rel="nofollow noopener noreferrer">
<svg xmlns="http://www.w3.org/2000/svg" aria-label="Mail" role="img" viewBox="0 0 512 512"><rect width="512" height="512" rx="15%" fill="#328cff"/><path d="m250 186c-46 0-69 35-69 74 0 44 29 72 68 72 43 0 73-32 73-75 0-44-34-71-72-71zm-1-37c30 0 57 13 77 33 0-22 35-22 35 1v150c-1 10 10 16 16 9 25-25 54-128-14-187-64-56-149-47-195-15-48 33-79 107-49 175 33 76 126 99 182 76 28-12 41 26 12 39-45 19-168 17-225-82-38-68-36-185 67-248 78-46 182-33 244 32 66 69 62 197-2 246-28 23-71 1-71-32v-11c-20 20-47 32-77 32-57 0-108-51-108-108 0-58 51-110 108-110" fill="#fff"/></svg>
</a>
<a href="https://github.com/boyaziqi" title="catsaction Github Repository" target="_blank" rel="nofollow noopener noreferrer">
<svg xmlns="http://www.w3.org/2000/svg" aria-label="GitHub" role="img" viewBox="0 0 512 512"><rect width="512" height="512" rx="15%" fill="#1B1817"/><path fill="#fff" d="M335 499c14 0 12 17 12 17H165s-2-17 12-17c13 0 16-6 16-12l-1-50c-71 16-86-28-86-28-12-30-28-37-28-37-24-16 1-16 1-16 26 2 40 26 40 26 22 39 59 28 74 22 2-17 9-28 16-35-57-6-116-28-116-126 0-28 10-51 26-69-3-6-11-32 3-67 0 0 21-7 70 26 42-12 86-12 128 0 49-33 70-26 70-26 14 35 6 61 3 67 16 18 26 41 26 69 0 98-60 120-117 126 10 8 18 24 18 48l-1 70c0 6 3 12 16 12z"/></svg>
</a>
<a href="https://www.linkedin.com/feed/" title="My LinkedIn" target="_blank" rel="nofollow noopener noreferrer">
<svg xmlns="http://www.w3.org/2000/svg" aria-label="LinkedIn" role="img" viewBox="0 0 512 512" fill="#fff"><rect width="512" height="512" rx="15%" fill="#0077b5"/><circle cx="142" cy="138" r="37"/><path stroke="#fff" stroke-width="66" d="M244 194v198M142 194v198"/><path d="M276 282c0-20 13-40 36-40 24 0 33 18 33 45v105h66V279c0-61-32-89-76-89-34 0-51 19-59 32"/></svg>
</a>
</div>
<h4>Friendship Links</h4>
<ul class="list-of-tags tags-in-article">
<li>
<a href="https://leetcode-cn.com/" title="力扣中国站点" target="_blank" rel="nofollow noopener noreferrer">
LeetCode
</a>
</li>
<li>
<a href="https://coolshell.cn/about" title="陈皓酷壳" target="_blank" rel="nofollow noopener noreferrer">
CoolShell
</a>
</li>
<li>
<a href="https://yikun.github.io/" title="姜毅坤博客" target="_blank" rel="nofollow noopener noreferrer">
Yikun
</a>
</li>
<li>
<a href="https://www.nowcoder.com/" title="牛客网" target="_blank" rel="nofollow noopener noreferrer">
牛客网
</a>
</li>
</ul>
</section>
</div>
</article>
</div>
<div class="span1"></div>
</div>
</div>
</div>
<footer>
<div>
<span class="site-name">CatsAction's blog</span> - It's a wonderful world
</div>
<div id="fpowered">
Powered by: <a href="http://getpelican.com/" title="Pelican Home Page" target="_blank" rel="nofollow noopener noreferrer">Pelican</a>
Theme: <a href="https://elegant.oncrashreboot.com/" title="Theme Elegant Home Page" target="_blank" rel="nofollow noopener noreferrer">Elegant</a>
</div>
</footer> <script src="//code.jquery.com/jquery.min.js"></script>
<script src="//netdna.bootstrapcdn.com/twitter-bootstrap/2.3.2/js/bootstrap.min.js"></script>
<script>
function validateForm(query)
{
return (query.length > 0);
}
</script>
<script>
(function () {
if (window.location.hash.match(/^#comment-\d+$/)) {
$('#comment_thread').collapse('show');
}
})();
window.onhashchange=function(){
if (window.location.hash.match(/^#comment-\d+$/))
window.location.reload(true);
}
$('#comment_thread').on('shown', function () {
var link = document.getElementById('comment-accordion-toggle');
var old_innerHTML = link.innerHTML;
$(link).fadeOut(200, function() {
$(this).text('Click here to hide comments').fadeIn(200);
});
$('#comment_thread').on('hidden', function () {
$(link).fadeOut(200, function() {
$(this).text(old_innerHTML).fadeIn(200);
});
})
})
</script>
</body>
<!-- Theme: Elegant built for Pelican
License : MIT -->
</html>