# yum install memcached.x86_64 php-pecl-memcache.x86_64
Edit /etc/sysconfig/memcached file, enter
# vi /etc/sysconfig/memcached
Sample outputs
PORT="11211" USER="memcached" MAXCONN="1024" CACHESIZE="64" OPTIONS="
For busy servers you need to increase the values as follows:
MAXCONN: Use 1024 max simultaneous connections; the default is 1024. For busy server increase this number as per requirements.
CACHESIZE: Use 64 MB memory max to use for object storage; the default is 64 megabytes. For busy server you can set it to 512MB or 1GB (1024).
OPTIONS: You can set server IP address (listen on address) here so that apache/php/nginx based serer can connect to the server. By default it is set to INADDR_ANY. This is an important option to consider as there is no other way to secure the installation. Binding to an internal or firewalled network interface is suggested.
PORT="11211" USER="memcached" MAXCONN="4096" CACHESIZE="512" OPTIONS="-l 192.168.1.15"
Type the following commands
# /etc/init.d/memcached start # /etc/init.d/memcached stop # /etc/init.d/memcached restart # /etc/init.d/memcached status
Type the following command to see if it is running or not
# pgrep memcached # netstat -tulpn | grep :11211
Sample outputs
tcp 0 0 192.168.1.15:11211 0.0.0.0:* LISTEN 24964/memcached udp 0 0 192.168.1.15:11211 0.0.0.0:* 24964/memcached
Use the memcached-tool to get general stats
# memcached-tool 192.168.1.15:11211 stats
Sample outputs
#192.168.1.15:11211 Field Value
accepting_conns 1
auth_cmds 0
auth_errors 0
bytes 5481902
bytes_read 8242409
bytes_written 26023492
cas_badval 0
cas_hits 0
cas_misses 0
cmd_flush 0
cmd_get 9042
cmd_set 4469
conn_yields 0
connection_structures 48
curr_connections 47
curr_items 3197
decr_hits 0
decr_misses 0
delete_hits 6
delete_misses 112
evictions 0
get_hits 7490
get_misses 1552
incr_hits 0
incr_misses 0
limit_maxbytes 536870912
listen_disabled_num 0
pid 24964
pointer_size 64
rusage_system 0.149977
rusage_user 0.043993
threads 4
time 1327395688
total_connections 171
total_items 3226
uptime 198
version 1.4.4
Make sure iptables only allows access to your own servers. Edit /etc/sysconfig/iptables and append the following rules or add it as follows to your shell scripts
## add to your shell script ## ## assumption default INPUT policy is set to DROP ## ## only accept connection to tcp/udp port 11211 if ip is between 192.168.1.10 and 192.168.1.15 ## iptables -A INPUT -p tcp --destination-port 11211 -m state --state NEW -m iprange --src-range 192.168.1.10-192.168.1.15 -j ACCEPT iptables -A INPUT -p udp --destination-port 11211 -m state --state NEW -m iprange --src-range 192.168.1.10-192.168.1.15 -j ACCEPT
