Zabbix question: Cannot allocate shared memory of size

Problem Status:

ZABBIX_AGENTD cannot start, system CentOS 5.8 i386

Cause Analysis:

This is due to the kernel's limitations on share memory.

Use the following command IPCS [-M|L|A],SYSCTL [-a|p]

1

[root@server01 ~]# ipcs-l < Span class= "Crayon-o" ><br/><br/><p></p> <p>------Shared Memory Limits--------<br/>max number of segments = 4096 <strong><br/>max seg s Ize (Kbytes) = 0<br/>max Total shared memory (Kbytes) = 0</strong><br/>min seg size (bytes) = 1</p& gt;<p>------Semaphore Limits--------<br/>max number of arrays = 128<br/>max semaphores per array = 2 50<BR/>max semaphores system wide = 32000<br/>max ops per semop call = 32<br/>semaphore max value = 3 2767</p><p>------messages:limits--------<br/>max queues system wide = 16<br/>max size of mess Age (bytes) = 65536<br/>default max size of queue (bytes) = 65536</p>

 

You can see from above that Max Total shared memory and Max SEG size are unlimited. But Zabbix still can't allocate memory.

Next, look at the current shared memory settings,

1	[root@server01 ~]# sysctl-a|grep shm<br/>kernel.shmmni = 4096<br/> Kernel.shmall = 0<br/>kernel.shmmax = 0

Where Kernel.shmall represents the total amount of shared memory that can be allocated, Kernel.shmax represents the memory (in bytes) that a single segment can allocate, which is 0, so there must be a problem.

Then view/etc/sysctl.conf

1	Kernel. Shmmax = 68719476736<br />kernel. Shmall = 4294967296

Get Shmall for 4g,shmax larger, 64G, because is 32-bit system, so set shmall time can not more than 32-bit system to recognize the maximum memory, so can be set to more than 3G, so this I instead

1	Kernel. Shmmax = 1294967296<br />kernel. Shmall = 3294967296

Then perform sysctl-p to take effect, and then look at the following.

1	[root@server01 ~]# sysctl-a|grep shm<br/>kernel.shmmni = 4096<br/> Kernel.shmall = 3294967296<br/>kernel.shmmax = 1294967296

It does take effect, then start zabbix_agentd successfully, and check the memory allocations as follows.

1

[Root@Server01 ~]# ipcs-m<br/><br/><p></p><p>----- -Shared Memory segments--------<br/>key        shmid       owner      perms       bytes      nattch     status      &NBSP;<BR/>0x7401840e 2916352    root      600         4          0                         <br/>0X6C0180CF 3047425    zabbix    600         527272     6  </p>

In fact, not only Zabbix, many programs this error can also be used to solve the problem, because the kernel of the resource constraints.

Zabbix question: Cannot allocate shared memory of size