Hey guys,
OK so I'm pretty familiar with how to edit an init script for memcached so
that I can get multiple memcached 'buckets' when starting up the
service.
The init script would ususally have multiple lines such as these under the
start function:
# cache_block
/usr/local/bin/memcached -d -m 128 -l `hostname -i` -p 11318 -u
daemon -c 8172 -v 2>> /tmp/memcached.log
# cache_filter
/usr/local/bin/memcached -d -m 512 -l `hostname -i` -p 11319 -u
daemon -c 8172 -v 2>> /tmp/memcached.log
# cache_form
/usr/local/bin/memcached -d -m 128 -l `hostname -i` -p 11320 -u
daemon -c 8172 -v 2>> /tmp/memcached.log
Now, under CentOS 7, I see we have two files controlling memcached under
the new sysctl system. At least, using sysctl is new to me!
I see we have this file:
[root at web1:~] #cat /usr/lib/systemd/system/memcached.service
[Unit]
Description=Memcached
Before=httpd.service
After=network.target
[Service]
Type=simple
EnvironmentFile=-/etc/sysconfig/memcached
ExecStart=/usr/bin/memcached -u $USER -p $PORT -m $CACHESIZE -c $MAXCONN
$OPTIONS
[Install]
WantedBy=multi-user.target
And we have this one under sysconfig:
[root at web1:~] #cat /etc/sysconfig/memcached
PORT="11211"
USER="memcached"
MAXCONN="1024"
CACHESIZE="64"
OPTIONS=""
So I'm trying to figure out how to achive the same effect that I would
under the old init script way of doing things.
Can someone please give me an example of how to get the same thing done
under the new system?
Thanks,
Tim
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Alberto Rivera Laporte
2015-Mar-18 05:06 UTC
[CentOS] multiple memcached buckets in CentOS 7
> > > Now, under CentOS 7, I see we have two files controlling memcached under > the new sysctl system. At least, using sysctl is new to me! > > I see we have this file: > > [root at web1:~] #cat /usr/lib/systemd/system/memcached.service > [Unit] > Description=Memcached > Before=httpd.service > After=network.target > > [Service] > Type=simple > EnvironmentFile=-/etc/sysconfig/memcached > ExecStart=/usr/bin/memcached -u $USER -p $PORT -m $CACHESIZE -c $MAXCONN > $OPTIONS > > [Install] > WantedBy=multi-user.target > > And we have this one under sysconfig: > > [root at web1:~] #cat /etc/sysconfig/memcached > PORT="11211" > USER="memcached" > MAXCONN="1024" > CACHESIZE="64" > OPTIONS="" > > So I'm trying to figure out how to achive the same effect that I would > under the old init script way of doing things. > > Can someone please give me an example of how to get the same thing done > under the new system? > >As you said earlier on earlier ( non-systemd) versions of the memcached init scripts, you would define all instances of memcache under the start function. With systemd it will be as easy as creating additional unit files ( one for each memcached instance) with its corresponding config file. That should allow to stop / start / restart each memcache instance individually while also being systemd compliant. Examples: ## first instance ## # /usr/lib/systemd/system/memcached.service [Unit] Description=Memcached Before=httpd.service After=network.target [Service] Type=simple EnvironmentFile=-/etc/sysconfig/memcached ExecStart=/usr/bin/memcached -u $USER -p $PORT -m $CACHESIZE -c $MAXCONN $OPTIONS # /etc/sysconfig/memcached PORT="11211" USER="memcached" MAXCONN="1024" CACHESIZE="64" OPTIONS="" ## end first instance ## second instance ## ## second instance ## # /usr/lib/systemd/system/memcached-11214.service [Unit] Description=Memcached-11214 Before=httpd.service After=network.target [Service] Type=simple EnvironmentFile=-/etc/sysconfig/memcached-11214 ExecStart=/usr/bin/memcached -u $USER -p $PORT -m $CACHESIZE -c $MAXCONN $OPTIONS # /etc/sysconfig/memcached-11214 PORT="11214" USER="memcached" MAXCONN="1024" CACHESIZE="64" OPTIONS="" ## end second instance Lastly enable each service if not already enabled: # instance 1 systemctl enable /usr/lib/systemd/system/memcached.service systemctl start memcached.service # instance 2 systemctl enable /usr/lib/systemd/system/memcached-11214.service systemctl start memcached-11214.service You can also still use legacy sysv init scripts as there is support for backwards compatibility however the systemd approach is much simpler while adhering to the systemd standard. Good luck.
Hi Alberto, With systemd it will be as easy as creating additional unit files ( one for> each memcached instance) with its corresponding config file. That should > allow to stop / start / restart each memcache instance individually while > also being systemd compliant.Thanks for the info and for the examples. It really does make sense the way you explain it. Thanks for letting me know! Best regards, Tim On Wed, Mar 18, 2015 at 1:06 AM, Alberto Rivera Laporte <arlaporte at gmail.com> wrote:> > > > > > Now, under CentOS 7, I see we have two files controlling memcached under > > the new sysctl system. At least, using sysctl is new to me! > > > > I see we have this file: > > > > [root at web1:~] #cat /usr/lib/systemd/system/memcached.service > > [Unit] > > Description=Memcached > > Before=httpd.service > > After=network.target > > > > [Service] > > Type=simple > > EnvironmentFile=-/etc/sysconfig/memcached > > ExecStart=/usr/bin/memcached -u $USER -p $PORT -m $CACHESIZE -c $MAXCONN > > $OPTIONS > > > > [Install] > > WantedBy=multi-user.target > > > > And we have this one under sysconfig: > > > > [root at web1:~] #cat /etc/sysconfig/memcached > > PORT="11211" > > USER="memcached" > > MAXCONN="1024" > > CACHESIZE="64" > > OPTIONS="" > > > > So I'm trying to figure out how to achive the same effect that I would > > under the old init script way of doing things. > > > > Can someone please give me an example of how to get the same thing done > > under the new system? > > > > > As you said earlier on earlier ( non-systemd) versions of the memcached > init scripts, you would define all instances of memcache under the start > function. > > With systemd it will be as easy as creating additional unit files ( one for > each memcached instance) with its corresponding config file. That should > allow to stop / start / restart each memcache instance individually while > also being systemd compliant. > > > Examples: > > ## first instance ## > # /usr/lib/systemd/system/memcached.service > [Unit] > Description=Memcached > Before=httpd.service > After=network.target > > [Service] > Type=simple > EnvironmentFile=-/etc/sysconfig/memcached > ExecStart=/usr/bin/memcached -u $USER -p $PORT -m $CACHESIZE -c $MAXCONN > $OPTIONS > > # /etc/sysconfig/memcached > PORT="11211" > USER="memcached" > MAXCONN="1024" > CACHESIZE="64" > OPTIONS="" > ## end first instance > > ## second instance ## > > ## second instance ## > # /usr/lib/systemd/system/memcached-11214.service > [Unit] > Description=Memcached-11214 > Before=httpd.service > After=network.target > > [Service] > Type=simple > EnvironmentFile=-/etc/sysconfig/memcached-11214 > ExecStart=/usr/bin/memcached -u $USER -p $PORT -m $CACHESIZE -c $MAXCONN > $OPTIONS > > # /etc/sysconfig/memcached-11214 > PORT="11214" > USER="memcached" > MAXCONN="1024" > CACHESIZE="64" > OPTIONS="" > ## end second instance > > Lastly enable each service if not already enabled: > # instance 1 > systemctl enable /usr/lib/systemd/system/memcached.service > systemctl start memcached.service > > # instance 2 > systemctl enable /usr/lib/systemd/system/memcached-11214.service > systemctl start memcached-11214.service > > You can also still use legacy sysv init scripts as there is support for > backwards compatibility however the systemd approach is much simpler while > adhering to the systemd standard. > > Good luck. > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos >-- GPG me!! gpg --keyserver pool.sks-keyservers.net --recv-keys F186197B