Hardware :: Test Memory During Centos/RHEL Installation?
Apr 8, 2011
I have been battling an issue for a couple of days and I have it down to 2 possibilities. Memory or mobo. A server in the DC is being very sketchy. Sometimes it will boot fine, sometimes it will boot but will not show all the memory, and sometimes it will hang before it even posts. I have replaced just about everything inside the system except for the memory and the mobo.
I would like to test the memory before replacing either because both are a few hundred dollars. The problem is, the memory doesn't log any errors and running a memory test with ubcd doesn't work because it's ecc memory. I thought I remembered hearing that there is a way to run a memory test during a Centos or RHEL installation, but I can't figure out how.
I install CentOS5.5 on VMWARE,the system is working properly.I want to test reinstall CentOS5.5 on VMWARE,So,I make a snapshot.My system partition（Manually partition ）is:/(1G),/boot(512M),swap(2G),/usr(30G),/var(10G),/data(20G).Each partition is independent of the ] partition.I reinstall CentOS5.5 by CentOS5.5.ISO.I format / partition,and other partition unchanged.However, the installation process was wrong:
I've got this really weird problem and I'm not even sure if it is a problem. I recently upgraded the RAM on my Compaq Presario Laptop from 3GB to 4GB by swapping out a 1GB DDR to a 2GB DDR so now it contains two 2GB DDRs. The BIOS shows 4096 MB of memory, Fedora shows 3955MB (Probably after the reduction for the video memory) so that's fine.
But I noticed a very quick flash during boot in between the Compaq Screen and GRUB. It only started coming after the RAM upgrade. I'm not able to make out what exactly is written. It's too fast. Will try with a proper camera at home. In any case, I could make out some large number probably in the order of gigabytes written in bytes. Again, not sure of the exact value.
So I get a little curious about this message and decide to run a memory test. It's working perfectly. Around 74%, it stops and says Memory Test Passed and moves on to check the HDD. I try the same from the BIOS. In the BIOS, it's a progress bar and no percentage value mentioned. Though the BIOS says 4096MB of memory, the progress bar also stops at roughly 75% and says passed. I'm not even sure what to search for on Google though I tried and got no similar results.
why this is happening? Since it's stopping at 75%, I have a feeling that the change in the amount of RAM hasn't been made in some place by the system.
this is a dual boot XP/UBUNTU 10.04. while using XP, the computer rebooted itself. the GRUB's screen appears, but neither the ubuntu nor the XP option works.
Ubuntu gives this error message:
Code: 0.797795 kernel panic-not syncing: vfs: enable to mount root fs on unknown-block (0,0)
XP hangs on a black screen... and that is it (thanks for support windows!) UBUNTU 10.04 live CD hangs when the 5 processing dots appears bellow the ubuntu logo. hangs the same way with the processing bar in UBUNTU 9.04 live CD. memory check (memtest86) is showing thousands of errors right from the start.
I am trying to install mysql 5.1.44..so i downloaded the binary package, i extracted it and then followed the instructions that were in the manual but i keep getting this error when running this command
Installing MySQL system tables... 100315 20:07:27 [Warning] Can't create test file /var/lib/mysql/mosty.lower-test 100315 20:07:27 [Warning] Can't create test file /var/lib/mysql/mosty.lower-test
A client has sent me an RHEL 5.1 box for me to do some work on, but it's not registered with Red Hat. This is causing me problems, because it's a minimal installation, and I need some more dev software.My immediate reaction was to install various bits (emacs, and so on) from my Centos 5(.0) DVD.The base RHEL system only had one (disabled) repo entry,so I added a yum DVD repo entry in yum.conf.d.
This looked good to start with, but it doesn't work. Something in RHEL's pirut/yum/rpm/whatever is getting confused, and can't work out what is/isn't installed.
Question - how do you maintain an unregistered RHEL box? Has RH done something to make life difficult? Is my problem simply that I'm using a Centos 5.0 DVD, instead of Centos 5.1? Am I stuck with downloading lots of rpms from the net and doing everything manually? I really don't want to do that.
I'm very new to Linux but when I first installed it, I downloaded the Start-Up Manager so I could change the boot order. I have a dual boot Windows-Linux, I set the default as Windows. Recently my computer started booting to the system memory test in the grub menu instead of Windows. When I try to open the Start-Up Manager now it asks me for the password as usual and then does not start. How I would change it back to windows for the default? I'm running Ubuntu 9.10.
i have new build testing centos 5.4 i386 base how to monitor logs and watch what is going wrong with file. i have 1 zmanda server enterprise i give permission and when i excecute nothing happend
Note : Test it on Test Machine before you do it on live server O.S : RHEL 5 / CENTOS 5 FYI.... OR IDEA If you wish to install only jre download & install jre-6u18-linux-i586-rpm.bin in /usr/java ( Note create java dir { mkdir /usr/java }
I have been doing a lot of research on the web to piece together the components I need to understand what is probably a very simple thing. I've read up on buffers/cache vs. physical memory and using free -m and top and understanding that output, and reviewed Red Hat's article on virtual memory. I am hoping to get some assistance in putting it all together to understand what's happening in my situation because so far I have a lot of dangling factoids and no glue. I have also referenced the thread http://www.linuxquestions.org/questi...memory-309767/ but I didn't find my answer there.
My company is running a cluster of physical web servers (they are clones so running the same OS, with same RAM and applications installed). I'll be referring to a single system although the question applies to all because they're all showing similar output. The Multi Router Traffic Grapher is showing a steady swap usage for 3-4 months now. The average usage for today is 81%. There is, as far as I know, no performance hit because of it, but a developer noticed this and wanted to know what was going on, and I'd using this opp to learn. The system is Linux version 2.6.18-128.7.1.el5, running JBOSS, postgres, Apache, and Java. Here is the output from the memory commands I have used to try and understand what's going on.
So my interpretation of this output tells me that my system has 4GB of RAM installed, 23MB of free "physical" RAM, and 1.35GB of RAM in cache (according to the second line of free -m, which represents free physical memory and useable mapped memory if I understand correctly). I have a 2GB swap partition, 1.5GB of which is currently being used, and according to the MRTG is the average that has been in use since January. So the swap size isn't decreasing. Java (JBOSS) is using the most physical RAM at 1.6GB.
My question is: if I have 1.35GB of RAM cached, why is my system using all of that swap space and not using any of the cached RAM? I thought I understood that Linux is supposed to either re-use unmodified pages in cache or send older pages to disk when more RAM was needed. It seems like my system is always sending pages to disk, which I guess would normally mean I just need more RAM but, to have close to the same swap size consistently seems like there must be more to it.
i opened up my browser to surf the web and a page popped up i had never seen before.Apache 2 Test page powered by centos. Any address i put into my firefox browser won't come up and i'm stuck on this test page and,i can't locate it on my computer to remove it.How do i get rid of it and more importantly how did it get on my computer in the first place?
I am trying to run though the qmailrocks setup on a centos 5.5 and I am running into an issue when trying to telnet to port 25:
telnet localhost 25 Trying 127.0.0.1... Connected to localhost.localdomain (127.0.0.1). Escape character is '^]'. Connection closed by foreign host.
Everything else seems to be working (telnet to 110), and I turned off the firewall entirely, but I still cannot telnet to port 25. I also get a blank error within squirrelmail when attempting to send mail out (ERROR:Message not sent. Server replied: ). I apologize for not going directly to the qmailrocks forum, but they are currently closed down (due to lack of funds). I also am a newbie, so I apologize for the lack of needed information. If anyone has any ideas, please let me know what information you would need.
I am trying to set up autofs in RHEL 5 and every time I run the "automount" command, I receive this message: "automount: test mount forbidden or incorrect kernel protocol version, kernel protocol version 5.00 or above required."
I am trying to see if there is an authbind equivalent or authbind package for CentOS/RHEL? x If so, where can I get more info and download it? It seems to be only available for Debian and Ubuntu.
We are slowly migrating from a predominantly Windows house to a 50/50 Win/RHEL operation and even further in the future.Currently, we have a LOT of Windows folders that are created by custom applications which, upon creation of a new folder set, applies the corresponding ACL so that only the associated groups are able to access the folders. Now for the problem, we are migrating the applications to a RHEL55 environment and it is creating the folders on that system now but the groups are still residing in the Windows AD. Is there an "easy" (I know, a very relative term) to have the Windows groups given permission to the Linux shares without very much manual intervention?
Is there a system admin tool for RHEL on montioring and logging system memory used and released that can dump to a log file?I'm having an issue with memory not being released when an application is closed. I need to have a tool monitor and log so I can troubleshoot to verify that it's an application not the OS.
I just ran into a weird problem with a CentOS 5.5 64-bit server running VirtualBox 3.2.8 (I would run Vmware Server 2.0.2 if not for the well known fact that Vmware doesn't care about its Server line anymore and it doesn't run on CentOS > 5.3 without major splits). I currently have two guests in that VirtualBox setup, a CentOS 5.5 64-bit and a Fedora 13 64-bit. The CentOS 5.5 guest shows less memory available than configured. If, for example, I give the virtual machine 512MB of memory the guest OS only recognizes 380MB. If I give it 768MB it only recognizes 637MB, and so on. I don't have that problem on the Fedora guest - 1024MB configured, 1024MB available.
We've been having lots of problems with burning CD-Rs on our Dell PowerEdge and T300 servers. We've had the CD recorders replaced frequently, and that often fixes the problem, but then we'll start having problems again. Usually it is the CD refuses to write, or it gets written but can't be read. Often, if I re-run the burn with the same blank CD, it will be fine.
I'd like to test some CD-Rs and compare error rates so I can recommend what CD-R media we should be using. Currently we are using Memorex and Verbatim CD-Rs. Is there a good cd recording/testing suite for Linux that I could use to do this?
I am trying to search a tool for testing multicast. Currently, 'yum search multicast' yields nothing. I saw mcsender and mctest in google but they seem not to be supported in CentOS. Do you know any tool that can test multicast?
I've been trying to install VSFTP on a test box I have at home. Here are the steps that I've done so far: First, I install vsftpd via yum. yum install vsftpd
Newbie on the block with Centos 5.3 on a test server and and Ubuntu on a test workstation Note the wiki on VNC for a windows workstation but presume I could do this more easily from "Jaunty" (Ubuntu v 9.04)
I have Centos 5.3 installed on my pc. I have mysql, PHP and apache server running on my computer too.Is there any way I can test my website on my pc without running any stack ( lampp )?
