topic Re: Redhat AS3 U5, kernal parameters setup. in Operating System - Linux

Redhat AS3 U5, kernal parameters setup.

Silver_1 — Thu, 11 May 2006 18:04:09 GMT

Hi,

For installing a third party replication software i need to put the following kernal parameters. I new to Linux but an HP UX admin for 11 years.
I do know that i need to update this on /etc/sysctl.conf file.
----
Current /etc/sysctl.conf.

# Disables packet forwarding
net.ipv4.ip_forward = 0
# Enables source route verification
net.ipv4.conf.default.rp_filter = 1
# Disables the magic-sysrq key
kernel.sysrq = 0
kernel.sem=1010 32000 100 128
kernel.shmmax=4082577408
kernel.shmmni=4096
kernel.shmall=2097152
fs.file-max=409200
net.core.rmem_default=262144
net.core.rmem_max=262144
net.core.wmem_default=262144
net.core.wmem_max=262144
net.ipv4.ip_local_port_range = 1024 65000
---------------------
I need to set these for the special software....

semmni requires 70
semmns requires 255
semmnu requires 255
semmsl requires min 128
semopm requires 64
semume requires 255
shmmax requires 60MB
shmmin requires 1mb
shmmni requires 100
shmseg requires 26

Thanks,
Ajith

Re: Redhat AS3 U5, kernal parameters setup.

Steven E. Protter — Thu, 11 May 2006 18:30:12 GMT

Shalom,

Most of this stuff is in the /proc/sys folder

Example
[root@bersheva kernel]# more shmmni
4096
[root@bersheva kernel]# pwd
/proc/sys/kernel
[root@bersheva kernel]#

to change a parameter, normally use echo and redirect the output to that parameter.

echo 5030 > /proc/sys/kernel/shmmni

Check the values prior to overwriting. They may be high enough already.

SEP

Re: Redhat AS3 U5, kernal parameters setup.

Silver_1 — Thu, 11 May 2006 18:46:15 GMT

Thanks for your reply.

i have checked the same and was unable to get some of them on the directory..
eg:

[root@linux1 kernel]# pwd
/proc/sys/kernel
[root@linux1 kernel]# more semume
semume: No such file or directory
[root@linux1 kernel]# more semmnu
semmnu: No such file or directory
[root@linux1 kernel]# more semmsl
semmsl: No such file or directory
[root@linux1 kernel]# more shmseg
shmseg: No such file or directory
[root@linux1 kernel]# more semopm
semopm: No such file or directory
[root@linux1 kernel]#

Any idea ......

Re: Redhat AS3 U5, kernal parameters setup.

Stuart Browne — Thu, 11 May 2006 23:46:19 GMT

Most of those names look like HP-UX semephore and shared memory names. Most of them don't exist on a Unix platform.

You've already found that 'shmmax' and 'shmmni' are there, but the rest are tied up in other places.

Taken from http://www.akadia.com/services/ora_linux_install_10g.html :

Needed Check with
-----------------------------------------------------------------------------
shmmax = 2147483648 cat /proc/sys/kernel/shmmax
shmmni = 4096 cat /proc/sys/kernel/shmmni
shmall = 2097152 cat /proc/sys/kernel/shmall
shmmin = 1 ipcs -lm |grep "min seg size"
semmsl = 250 cat /proc/sys/kernel/sem | awk '{print $1}'
semmns = 32000 cat /proc/sys/kernel/sem | awk '{print $2}'
semopm = 100 cat /proc/sys/kernel/sem | awk '{print $3}'
semmni = 128 cat /proc/sys/kernel/sem | awk '{print $4}'
file-max = 65536 cat /proc/sys/fs/file-max
ip_local_port_range = 1024 65000 cat /proc/sys/net/ipv4/ip_local_port_range

To set these using '/etc/sysctl.conf', add something similar to:

kernel.shmall = 2097152
kernel.shmmax = 2147483648
kernel.shmmni = 4096
kernel.sem = 250 32000 100 128
fs.file-max = 65536
net.ipv4.ip_local_port_range = 1024 65000

Tweak the values as required.