MySQL Replication 가끔 누락되는 데이터

MySQL Replication 가끔 누락되는 데이터


DB Master 와 Slave 서버로 Replication 으로 동기화 운영중인데

하루에 몇 건 정도는 싱크가 누락되는 것 같다.

이유가 무엇일까 궁금하다~

cron 으로 두 DB 의 테이블을 비교하는 스크립트를 돌려서 다르면 다시 맞춰주고 있지만

제대로 Replication 이 되면 얼마나 좋을까~

그냥 푸념해본다~

CentOS 7.x minimal ifconfig command not found

CentOS 7.x minimal ifconfig command not found

[root@localhost ~]# ifconfig
-bash: ifconfig: command not found

[root@localhost ~]# netstat
-bash: netstat: command not found

[root@localhost ~]# yum install net-tools
...
Dependencies Resolved

================================================================================
 Package         Arch         Version                          Repository  Size
================================================================================
Installing:
 net-tools       x86_64       2.0-0.17.20131004git.el7         base       304 k

Transaction Summary
================================================================================
Install  1 Package

Total download size: 304 k
Installed size: 917 k
Is this ok [y/d/N]: y
Downloading packages:
net-tools-2.0-0.17.20131004git.el7.x86_64.rpm              | 304 kB   00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : net-tools-2.0-0.17.20131004git.el7.x86_64                    1/1
  Verifying  : net-tools-2.0-0.17.20131004git.el7.x86_64                    1/1

Installed:
  net-tools.x86_64 0:2.0-0.17.20131004git.el7


Complete!

CentOS 6.x X Window 삭제

CentOS 6.x X Window 삭제

서버호스팅을 신청했더니 불필요한 X윈도우까지 설치가 되어 있네요.

삭제하는 방법은 yum 그룹리스트가 있는 확인하고 삭제하면 됩니다.

[root@vps ~]# yum grouplist "X Window System"
Loaded plugins: fastestmirror, security
Setting up Group Process
Loading mirror speeds from cached hostfile
 * base: mirror.oasis.onnetcorp.com
 * epel: mirror.premi.st
 * extras: mirror.oasis.onnetcorp.com
 * rpmforge: ftp.neowiz.com
 * updates: mirror.oasis.onnetcorp.com
Available Groups:
   X Window System
Done
[root@vps ~]# yum groupremove "X Window System"
Loaded plugins: fastestmirror, security
Setting up Group Process
Loading mirror speeds from cached hostfile
 * base: mirror.oasis.onnetcorp.com
 * epel: mirror.premi.st
 * extras: mirror.oasis.onnetcorp.com
 * rpmforge: ftp.neowiz.com
 * updates: mirror.oasis.onnetcorp.com
Resolving Dependencies
--> Running transaction check
---> Package hal.x86_64 0:0.5.14-14.el6 will be erased
--> Processing Dependency: hal >= 0.5.10 for package: hal-info-20090716-5.el6.noarch
--> Processing Dependency: hal = 0.5.14-14.el6 for package: hal-devel-0.5.14-14.el6.x86_64
--> Processing Dependency: hal for package: pm-utils-1.2.5-11.el6.x86_64
---> Package xorg-x11-server-utils.x86_64 0:7.7-14.el6 will be erased
---> Package xorg-x11-xauth.x86_64 1:1.0.9-1.el6 will be erased
---> Package xorg-x11-xinit.x86_64 0:1.0.9-14.el6 will be erased
--> Processing Dependency: xorg-x11-xinit >= 1.0.2-22.fc8 for package: imsettings-0.108.0-3.6.el6.x86_64
--> Running transaction check
---> Package hal-devel.x86_64 0:0.5.14-14.el6 will be erased
---> Package hal-info.noarch 0:20090716-5.el6 will be erased
---> Package imsettings.x86_64 0:0.108.0-3.6.el6 will be erased
---> Package pm-utils.x86_64 0:1.2.5-11.el6 will be erased
--> Processing Dependency: pm-utils for package: libvirt-client-0.10.2-62.el6.x86_64
--> Running transaction check
---> Package libvirt-client.x86_64 0:0.10.2-62.el6 will be erased
--> Processing Dependency: libvirt-qemu.so.0()(64bit) for package: libvirt-devel-0.10.2-62.el6.x86_64
--> Processing Dependency: libvirt.so.0()(64bit) for package: libvirt-devel-0.10.2-62.el6.x86_64
--> Processing Dependency: libvirt-client = 0.10.2-62.el6 for package: libvirt-devel-0.10.2-62.el6.x86_64
--> Processing Dependency: libvirt-client >= 0.9.12 for package: libvirt-java-0.4.9-1.el6.noarch
--> Running transaction check
---> Package libvirt-devel.x86_64 0:0.10.2-62.el6 will be erased
---> Package libvirt-java.noarch 0:0.4.9-1.el6 will be erased
--> Processing Dependency: libvirt-java = 0.4.9-1.el6 for package: libvirt-java-devel-0.4.9-1.el6.noarch
--> Running transaction check
---> Package libvirt-java-devel.noarch 0:0.4.9-1.el6 will be erased
--> Finished Dependency Resolution

Dependencies Resolved

================================================================================
 Package                    Arch        Version                Repository  Size
================================================================================
Removing:
 hal                        x86_64      0.5.14-14.el6          @base      1.2 M
 xorg-x11-server-utils      x86_64      7.7-14.el6             @base      364 k
 xorg-x11-xauth             x86_64      1:1.0.9-1.el6          @base       89 k
 xorg-x11-xinit             x86_64      1.0.9-14.el6           @base       71 k
Removing for dependencies:
 hal-devel                  x86_64      0.5.14-14.el6          @base       48 k
 hal-info                   noarch      20090716-5.el6         @base      311 k
 imsettings                 x86_64      0.108.0-3.6.el6        @base      813 k
 libvirt-client             x86_64      0.10.2-62.el6          @base       15 M
 libvirt-devel              x86_64      0.10.2-62.el6          @base      5.0 M
 libvirt-java               noarch      0.4.9-1.el6            @base       73 k
 libvirt-java-devel         noarch      0.4.9-1.el6            @base       15 k
 pm-utils                   x86_64      1.2.5-11.el6           @base      254 k

Transaction Summary
================================================================================
Remove       12 Package(s)

Installed size: 23 M
Is this ok [y/N]: y
Downloading Packages:
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
  Erasing    : libvirt-devel-0.10.2-62.el6.x86_64                          1/12
  Erasing    : libvirt-java-devel-0.4.9-1.el6.noarch                       2/12
  Erasing    : libvirt-java-0.4.9-1.el6.noarch                             3/12
  Erasing    : hal-devel-0.5.14-14.el6.x86_64                              4/12
  Erasing    : libvirt-client-0.10.2-62.el6.x86_64                         5/12
  Erasing    : hal-info-20090716-5.el6.noarch                              6/12
  Erasing    : hal-0.5.14-14.el6.x86_64                                    7/12
  Erasing    : pm-utils-1.2.5-11.el6.x86_64                                8/12
  Erasing    : imsettings-0.108.0-3.6.el6.x86_64                           9/12
  Erasing    : xorg-x11-xinit-1.0.9-14.el6.x86_64                         10/12
  Erasing    : 1:xorg-x11-xauth-1.0.9-1.el6.x86_64                        11/12
  Erasing    : xorg-x11-server-utils-7.7-14.el6.x86_64                    12/12
  Verifying  : xorg-x11-server-utils-7.7-14.el6.x86_64                     1/12
  Verifying  : pm-utils-1.2.5-11.el6.x86_64                                2/12
  Verifying  : xorg-x11-xinit-1.0.9-14.el6.x86_64                          3/12
  Verifying  : hal-info-20090716-5.el6.noarch                              4/12
  Verifying  : hal-devel-0.5.14-14.el6.x86_64                              5/12
  Verifying  : libvirt-client-0.10.2-62.el6.x86_64                         6/12
  Verifying  : 1:xorg-x11-xauth-1.0.9-1.el6.x86_64                         7/12
  Verifying  : imsettings-0.108.0-3.6.el6.x86_64                           8/12
  Verifying  : hal-0.5.14-14.el6.x86_64                                    9/12
  Verifying  : libvirt-java-devel-0.4.9-1.el6.noarch                      10/12
  Verifying  : libvirt-java-0.4.9-1.el6.noarch                            11/12
  Verifying  : libvirt-devel-0.10.2-62.el6.x86_64                         12/12

Removed:
  hal.x86_64 0:0.5.14-14.el6          xorg-x11-server-utils.x86_64 0:7.7-14.el6
  xorg-x11-xauth.x86_64 1:1.0.9-1.el6 xorg-x11-xinit.x86_64 0:1.0.9-14.el6

Dependency Removed:
  hal-devel.x86_64 0:0.5.14-14.el6        hal-info.noarch 0:20090716-5.el6
  imsettings.x86_64 0:0.108.0-3.6.el6     libvirt-client.x86_64 0:0.10.2-62.el6
  libvirt-devel.x86_64 0:0.10.2-62.el6    libvirt-java.noarch 0:0.4.9-1.el6
  libvirt-java-devel.noarch 0:0.4.9-1.el6 pm-utils.x86_64 0:1.2.5-11.el6

Complete!

UNISON Waiting for changes from server

UNISON Waiting for changes from server

unison 을 실행하였는데 "Waiting for changes from server" 메시지 출력 이후 한참 기다려도 끝이 안나는데 그래도 기다리면 결과가 나옵니다.

이유는 두 서버에 파일이 많으면 파일 비교 데이터를 생성하는 과정에서  시간이 걸리기 때문입니다.

서버 사양에 따라 다르겠지만 7기가 조금 넘은 분량인데 10분 정도 걸렸습니다.

# unison
Contacting server...
Connected [//mydomain2.com//home -> //mydomain1.com//home]
Looking for changes
Warning: No archive files were found for these roots, whose canonical names are:
        /home
        //mydomain1.com//home
This can happen either
because this is the first time you have synchronized these roots,
or because you have upgraded Unison to a new version with a different
archive format.

Update detection may take a while on this run if the replicas are
large.

Unison will assume that the 'last synchronized state' of both replicas
was completely empty.  This means that any files that are different
will be reported as conflicts, and any files that exist only on one
replica will be judged as new and propagated to the other replica.
If the two replicas are identical, then no changes will be reported.

If you see this message repeatedly, it may be because one of your machines
is getting its address from DHCP, which is causing its host name to change
between synchronizations.  See the documentation for the UNISONLOCALHOSTNAME
environment variable for advice on how to correct this.

Donations to the Unison project are gratefully accepted:
http://www.cis.upenn.edu/~bcpierce/unison

  Waiting for changes from server
Reconciling changes
Nothing to do: replicas have been changed only in identical ways since last sync.

CentOS 7.x lsyncd Error: Temporary or permanent failure on startup

CentOS 7.x lsyncd Error: Temporary or permanent failure on startup

# systemctl start lsyncd
Mon Mar 27 15:45:27 2017 Error: Temporary or permanent failure on startup of "/home/". Terminating since "insist" is not set.

Main Server

# cat /etc/ssh/sshd_config | grep PermitRoot

PermitRootLogin no

# vi /etc/ssh/sshd_config

#PermitRootLogin no

PermitRootLogin yes

# systemctl restart sshd

Backup Server

# ssh-keygen
# ssh-copy-id root@mainserverip
# systemctl start lsyncd

CentOS 7.x mod_cband compile error

CentOS 7.x mod_cband compile error

# ./configure
checking for gcc... no
checking for cc... no
checking for cc... no
checking for cl... no
configure: error: no acceptable C compiler found in $PATH
See `config.log' for more details.

# yum install gcc

# ./configure
checking for gcc... gcc
checking for C compiler default output file name... a.out
checking whether the C compiler works... yes
checking whether we are cross compiling... no
checking for suffix of executables...
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ANSI C... none needed
checking whether make sets $(MAKE)... yes
checking for apr_palloc in -laprutil... no
checking for an ANSI C-conforming const... yes
checking for apxs... no
checking for apxs2... no
configure: error: apxs missing

# yum install httpd-devel

# make

apxs -Wc,-Wall -Wc,-DDST_CLASS=3 -c src/mod_cband.c

/usr/lib64/apr-1/build/libtool --silent --mode=compile gcc -std=gnu99 -prefer-pic -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic  -DLINUX -D_REENTRANT -D_GNU_SOURCE -pthread -I/usr/include/httpd  -I/usr/include/apr-1   -I/usr/include/apr-1  -Wall -DDST_CLASS=3  -c -o src/mod_cband.lo src/mod_cband.c && touch src/mod_cband.slo

src/mod_cband.c: In function 'mod_cband_create_traffic_size':

src/mod_cband.c:1054:15: warning: comparison with string literal results in unspecified behavior [-Waddress]

     if ((unit != "" && unit[0] == 'G') || (unit == "" && kb >= mult*mult)) {

               ^

src/mod_cband.c:1054:49: warning: comparison with string literal results in unspecified behavior [-Waddress]

     if ((unit != "" && unit[0] == 'G') || (unit == "" && kb >= mult*mult)) {

                                                 ^

src/mod_cband.c:1058:15: warning: comparison with string literal results in unspecified behavior [-Waddress]

     if ((unit != "" && unit[0] == 'M') || (unit == "" && kb >= mult)) {

               ^

src/mod_cband.c:1058:49: warning: comparison with string literal results in unspecified behavior [-Waddress]

     if ((unit != "" && unit[0] == 'M') || (unit == "" && kb >= mult)) {

                                                 ^

src/mod_cband.c: In function 'mod_cband_get_dst':

src/mod_cband.c:1333:47: error: 'conn_rec' has no member named 'remote_ip'

     p.add.sin.s_addr = inet_addr(r->connection->remote_ip);

                                               ^

src/mod_cband.c: In function 'mod_cband_get_remote_host':

src/mod_cband.c:1362:10: error: 'struct conn_rec' has no member named 'remote_i '

     if (c->remote_ip != NULL)

          ^

src/mod_cband.c:1363:20: error: 'struct conn_rec' has no member named 'remote_i '

  addr = inet_addr(c->remote_ip);

                    ^

src/mod_cband.c:1365:10: error: 'struct conn_rec' has no member named 'remote_addr'

  addr = c->remote_addr->sa.sin.sin_addr.s_addr;

          ^

src/mod_cband.c: In function 'mod_cband_update_speed':

src/mod_cband.c:1905:19: warning: variable 'time_last_request' set but not used [-Wunused-but-set-variable]

     unsigned long time_last_request;

                   ^

src/mod_cband.c: In function 'mod_cband_check_connections_speed':

src/mod_cband.c:2963:19: warning: variable 'time_now' set but not used [-Wunused-but-set-variable]

     unsigned long time_now;

                   ^

apxs:Error: Command failed with rc=65536

.

make: *** [src/.libs/mod_cband.so] Error 1

# sed -i 's/remote_ip/client_ip/g' ./src/mod_cband.c

# sed -i 's/c->remote_addr/c->client_addr/g' ./src/mod_cband.c

# make

# make install

CentOS 7.x How to open 53 port

CentOS 7.x How to open 53 port


[root@vps log]# firewall-cmd --permanent --zone=public --add-service=dns
success
[root@vps log]# firewall-cmd --reload
success
[root@vps log]# firewall-cmd --list-all
public (active)
  target: default
  icmp-block-inversion: no
  interfaces: eth0
  sources:
  services: dhcpv6-client dns ftp http https mysql ssh
  ports:
  protocols:
  masquerade: no
  forward-ports:
  sourceports:
  icmp-blocks: echo-request
  rich rules:

[root@vps log]# netstat -ant | grep :53

tcp        0      0 127.0.0.1:53            0.0.0.0:*               LISTEN

how to remove

# firewall-cmd --permanent --zone=public --remove-service=dns