Need to change shared memory limit in shmmax

gssb · 08-26-2011, 09:24 AM

Hi all,

I am running CentOS 64 bit and I need to install some specific database software which requires a shared memory limit greater than 32 MB.

I want to change the value of shmmax to the equivalent of 128 MB.

Unfortunately I cannot write away my changes in vi with wq! due to error E212 Can't open file for writing.

I can also not chmod the file due to "Operation not permitted".

I am working as ROOT and ROOT owns this file.

Any way I can get around this?

Thanks
Glenn

harry edwards · 08-26-2011, 05:42 PM

What file are you trying change?

mrmnemo · 08-26-2011, 06:20 PM

this may sound really dumb...but

try lsattr. Not sure why anything would get set that way. We use at work to block people from making changes alot. then again, with out the specific steps need to reproduce your error it may be kinda hard to figure out.
EXAMPLE:

Code:

$ touch test.txt
o_o$ lsattr -V test.txt 
lsattr 1.41.11 (14-Mar-2010)
-----------------e- test.txt
0_o$ chattr -V +ia test.txt; ll test.txt 
chattr 1.41.11 (14-Mar-2010)
Flags of test.txt set as ----ia-----------e-
chattr: Operation not permitted while setting flags on test.txt
-rw-r--r-- 1 0_o 0_o 0 2011-08-26 18:38 test.txt
chattr 1.41.11 (14-Mar-2010)
Flags of test.txt set as ----ia-----------e-
chattr: Operation not permitted while setting flags on test.txt

So, if you see ia after running lsattr against your file that might be a bump in the road.

gssb · 08-29-2011, 03:07 AM

I will ask my virtual server supplier about my problem and see what they say. It could be a restriction that they only have control over.

I will report back any solution.