无线网络: 无线网络的安全协议上,WPA已经取代了WEP成为无限网络的主流技术。 )、用户数据报协议(UDP)(不可靠面向无连接的协议) 网际互联层(5): 网际协议(IP)、互联网组管理协议(IGMP)、互联网控制报文协议(ICMP)(ping) 网络接口层(6~7): 地址解析协议 raw6 0 0 :::58 :::* 7 son (192.168.172.145): icmp_seq=6 ttl=64 time=0.649 ms 64 bytes from son (192.168.172.145): icmp_seq=7 dad (192.168.172.146): icmp_seq=6 ttl=64 time=0.963 ms 64 bytes from dad (192.168.172.146): icmp_seq=7
1.网络通信基本单位 Byte(字节)是用于计量存储容量的一种计量单位 2.网络通信基础 模拟信号(易实现易干扰) 数字信号(难实现难干扰) 模拟信道 数字信道 3.调制技术 将数字信号转换成模拟信号 表示由正极到零电平,1表示由负极到零电平 双相码:不同方向的电平反转,低到高代表0,高到低代表1 不归零码NRZ:码元信号不回归零电平,出现1时,电平翻转,零不翻转,也称之为差分机制,是差分曼彻斯特编码的基础编码 降0升1(降1升0);编码效率50% 2.差分曼彻斯特编码 差分曼彻斯特编码是在曼彻斯特编码的基础上加上了翻转特性,遇1翻转,遇0不变,常用于令牌环网;编码效率50% 3.MLT-3编码 逢“1”跳变,
logstash的配置中加入了 stdout {codec=>rubydebug} 是为了方便在终端监视信息(在实际应用中完全没有必要),经过一番刷屏,最终停了下来
为了避免只能使用sudo来调用Docker,在软件安装过程中自动创建了docker组,并且在docker进程启动时赋权给了这个组的用户以docker socket的读写权限,所以只用将管理用户加入到docker组,就可以对docker进行使用了
完全删除某空间下的文件 [root@h101 copy]# ../qshell_linux_amd64 listbucket qiniucloud-goods list.video [root@h101 copy]# ../qshell_linux_amd64 batchdelete qiniucloud-goods list.video <DANGER> Input hdbiha to confirm operation: hdbiha All deleted! [root@h101
drwx------ 2 root root 61 Mar 21 22:57 doc drwx------ 2 root root 6 Mar 21 22:57 logs drwx------ 7
也可以定向的只dump一个表,但这个操作没法在shell中完成,只能在sqlite中完成
# systemctl get-default graphical.target [root@docker ~]# runlevel N 5 [root@docker ~]# Tip: Centos7
root@h101 memcached-1.4.24# ps fuax | grep mem
安装 [root@h102 nginx-1.9.5]# make install make -f objs/Makefile install make[1]: Entering directory `/usr/local/src/nginx-1.9.5' test -d '/usr/local/nginx' || mkdir -p '/usr/local/nginx' test -d '/usr/local/nginx/sbin' || mkdir -p '/usr/local/nginx/sbin'
这是由于没指定数据源产生的报错 虽然没有连接任何数据库,但从操作体验上来看,与直接操作一个mysql没有什么区别 Tip: 为什么用户名和密码是 test 呢,因为 conf/server.xml 有定义 <user name="test"> <property name="password">test</property> <property name="schemas">TESTDB</property> </user> <user name="user"> <property name="pas
安装snort-2.9.7.6 [root@h101 snort]# tar -zxvf snort-2.9.7.6.tar.gz snort-2.9.7.6/ snort-2.9.7.6/depcomp snort-2.9.7.6/tools/ snort-2.9.7.6/tools/u2streamer/ snort-2.9.7.6/tools/u2streamer/sf_error.h snort-2.9.7.6/tools/u2streamer/sf_error.c snort-2.9.7.6/t
注意到 {listeners,[{clustering,25672,”::”},{amqp,5672,”::”}]} 变成了 {listeners,[]} , 内存磁盘还有文件句柄部分也消失了
初始化 slots [root@h102 codis]# bin/codis-config slot help usage: codis-config slot init [-f] codis-config slot info <slot_id> codis-config slot set <slot_id> <group_id> <status> codis-config slot range-set <slot_from> <slot_to> <group_id> <status> codi
; -- end job file -- Here we have no global section, as we only have one job defined anyway. We want to use async io here, with a depth of4foreach file. We also increased the buffer size used to32KB and define numjobs to4to fork 4 identical jobs. The result is4 processes each randomly writing to their own 64MB file. Instead ofusing the above job file, you could have given the parameters on the command line. For this case, you would specify: $ fio --name=random-writers --ioengine=libaio --iodepth=4 --rw=randwrite --bs=32k --direct=0 --size=64m --numjobs=4When fio is utilized as a basis ofany reasonably large test suite, it might be desirable toshare a setof standardized settings across multiple job files. Instead of copy/pasting such settings, anysection may pull in an external .fio file with'includefilename' directive, asin the following example: ;-- start job file including.fio -- [global] filename=/tmp/test filesize=1m include glob-include.fio [test] rw=randread bs=4k time_based=1 runtime=10 include test-include.fio ; -- end job file including.fio -- ; -- start job file glob-include.fio -- thread=1 group_reporting=1 ; -- end job file glob-include.fio -- ; -- start job file test-include.fio -- ioengine=libaio iodepth=4 ; -- end job file test-include.fio -- Settings pulled into a section apply to that section only (except global section). Include directives may be nested in that any included file may contain further include directive(s). Include files may not contain [] sections. 4.1 Environment variables ------------------------- fio also supports environment variable expansion in job files. Any sub-string of the form "${VARNAME}" as part of an option value (in other words, on the right of the `='),willbeexpandedtothevalueoftheenvironmentvariablecalledVARNAME.Ifnosuchenvironmentvariableisdefined,orVARNAMEistheemptystring,theemptystringwillbesubstituted.Asanexample,let's look at a sample fio invocation and job file: $ SIZE=64m NUMJOBS=4 fio jobfile.fio ; -- start job file -- [random-writers] rw=randwr
127.0.0.1:2379 > Accept: */* > < HTTP/1.1 200 OK < Content-Type: application/json < X-Etcd-Cluster-Id: 7e27652122e8b2ae
ls2 ls2 就是携带了stat信息的ls [zk: localhost:2181(CONNECTED) 60] ls /def [] [zk: localhost:2181(CONNECTED) 61] ls2 /def [] cZxid = 0xe ctime = Thu Dec 03 14:57:27 CST 2015 mZxid = 0xf mtime = Thu Dec 03 15:42:21 CST 2015 pZxid = 0xe cversion = 0 dataVersion = 1 a
运行 准备配置文件 源码包中有一些示例,可以作为配置模板 [root@h102 ~]# ll /usr/local/src/haproxy/haproxy-1.6.3/examples/*.cfg -rw-rw-r-- 1 root root 3740 Dec 27 22:04 /usr/local/src/haproxy/haproxy-1.6.3/examples/acl-content-sw.cfg -rw-rw-r-- 1 root root 3042 Dec 27 22:04 /usr/local
基本的检索方法,时间范围的设定,自动刷新周期的设定,展示结果的分享,结果的保存,过滤条件的设定,jason定义条件,文档的内容查看,字段的统计设定,
这些模块都很实用, ngx_http_upstream_check_module 可以检查后端服务器的状态