I'm new to deian and linux in general. I have a project to build a web server. All is going well - have LAMP configured and now reading/learning about security. I've just done a netstat -tuan to look at what ports I have open. It gave me this. I've managed to find out what a mojrity of the ports are...some i'm not sure of. Just wondering if anyone could enlighten me by answering a few questions on my notes:
1. what are the ports with ???. Can i disable them? 2. how comes some ports are listed twice? Do i need to disable them more than once. 3. Are the notes i've made correct...can i remove the ones I'm thinking of removing?
I have a problem with scrn and keyboard freezes. This time it only threatened to crash, and I've noticed something in /var/log/ mssge that might lead to a solution (if I understood it)
Apr 5 06:42:04 Den-mint kernel: [ 233.209761] EXT4-fs (sdc1): warning: mounting fs with errors, running e2fsck is recommended It's imediate context is below.
When I connect my Treo 650 with a USB cable it works sometimes and not others. A little investigation showed that it always works when I see the Palm device listed in the output of lsusb. While trying to diagnose why it appears sometimes and not others, I discovered that it sometimes appears in /proc/bus/usb/devices and not in lsusb. I didn't think that was possible!
I've tried running kudzu (the Red Hat hardware discovery tool) and killing and restarting udevd.
I've got the F13 LiveCD that I was able to boot and use using the "nomodeset" boot option. From the desktop I'm trying to perform an Install to Hard Drive. I've read the Install from LiveCD post regarding the creation of a /boot partition and a / root partition. I've tried creating them without the LVM group and with. But every time I appempt to install I get...
An error occurred mounting device proc as /proc: mount failed: (9, None). This is a fatal error and the install cannot continue.
Hardware is a Sager 8887 (P4, 3.06HT, 60GB HDD, Radeon 9000 graphics adapter)
I'm looking to setup a transparent proxy, which (if I understand correctly) will allow me to monitor/control http traffic on my home lan with the use a log analyser.I'm planning on following this guide Yes... I'm cheap and don't wanna buy another NIC.My question: How does this all work? I get that http traffic goes to my server first, and then to the destination address, but how? What is stopping the other computers on my network from going straight to my router?Is my interpretation of a transparent proxy correct?
the difference between /proc and /sys? Also, When enabling public-key authentication using SSH, what file on the remote machine must be modified and how?
Red Hat Enterprise Linux Server release 5.4 (Tikanga) 2.6.18-164.11.1.el5xen (Xen release for virtualisation)
I'm trying to track down a problem with a utility that used to work and now hangs indefinitely. Since its hanging, I suspected a locking problem, and went to have a look for the process ids in /proc/locks; I get:
Now as near as I can tell this shouldn't be my problem, since the two ADVISORY locks - one READ and one WRITE - shouldn't conflict with one another. But I'd like to understand it all the same. I haven't been able to find any kind of definitive guide for the format of /proc/locks entries, but what I did find in the manuals specifically states:
"Each lock has its own line which starts with a unique number. "
Which is obviously not true; both of my lines start with the same number. Also, since most search engines don't seem to play nicely with symbols, I can't find any reference to what the "->" means.
I am currently writing a JAVA script to monitor certain unix processes through JConsole. Upon having lots of trouble with runtime.exec, i decided to bypass the top/ps command call and just get the information straight from /proc/*pid*/whatever.Now i can pull back any information from any of the files I want, and the current way i determine the CPU usage of a process is as follows:
Add the UTime and STime of that process from /proc/pid/stat then divide my pidCpu by UTime + STime + NTime from /proc/stat, then multiply that by 100, should give me the % cpu usage a process is using, right?Theory being if I get the jiffies assigned to my process, I can divide that by the total jiffies the cpu assigns. However, my results seem to vary from the ones gathered from top and ps. What am I doing wrong?
/proc/bus/usb/devices should not be used anymore (and can't be mounted anymore on Ubuntu 11.04) But what is an alternative to it, for use in a terminal? I could easily grep that output to look for a certain device, but I'm lost in all the /sys/ entries...
Is there a simple way to determine the CPU socket from the output of /proc/cpuinfo. Determining the type of processor is simple enough, but the processor I have (Celeron) has two different possible sockets. The output of /proc/cpuinfo is:
processor : 0 vendor_id : GenuineIntel cpu family : 15
[Code]...
I've looked on the Intel processor finder web site with appropriate filters, but the stepping values do not appear to match anything.
i had some issue with the machine rebooting multiple times, What happens is that the machine boots up and suddenly crashes and then boots up cleanly. I was going through the log files during when this occurs. I came across /var/log/syslog which i guess logs messages before shutdown. It has following messages which i think are causing problem.
Could not open /proc/26694/stat: No such file or directory Could not read the file /proc/26694/stat Could not open /proc/31128/stat: No such file or directory Could not read the file /proc/31128/stat
I'm working in CentOS 5.4 with the default 2.6.18-164 kernel (which I will be editing but have reverted back to in order to solve this problem.)
Near the end of the init script I have thrown a /bin/sh to get into a busybox bash shell in order to test some scripts. Ive attached the init below.
While in this shell I can see my usb drive in /proc/bus/usb/devices and my hard drive in /proc/scsi/device_info however I cannot mount them as they are not in /dev.
I have scsi emulation set in the kernel. When I plug in a USB stick it finds the address but still no sign of it in /dev. There are other modules listed in /sys/module such as usbcore that dont show up in lsmod, is that possibly the problem?
Init Script
Quote:
#!/bin/nash mount -t proc /proc /proc setquiet echo Mounting proc filesystem echo Mounting sysfs filesystem mount -t sysfs /sys /sys
where can i find the scheduler source core "sched.c" file inside ubuntu 9.10 file systemI need to study the scheduler functionality for my project purpose
My CPU has 2 cores, so I can see two parts in /proc/cpuinfo.But, I want to know if CPUs that support Hyper-Threading (or similar tech), will /proc/cpuinfo give CPU info per core or per thread (or call it sibling)?I only know that Windows Task Manager will give CPU usage statistics per thread if the CPU supports HT.
As I understand it, setting /proc/sys/vm/overcommit_memory to 1 is supposed to make sure malloc always succeeds, and set the OOM killer loose if there's an actual memory problem.
I'm wondering what happens when you've malloc'd so much memory that you've exhausted the address space for your process? Does it return NULL despite the overcommit_memory setting, or does your process get a signal? Or something else entirely?
I have a script that needs to extract certain information form the /proc/net/ip_conntrack file once in a while. I do not wish to run this script as the root user.
Default permissions for the file is:
I can change it with:
But that does not stick after a reboot. Is there some configuration file for file-permissions in the /proc directory in Ubuntu Server 9.10? Or do I just have to stick a chmod line in some startup script?
I'm interesting in knowing what processes could be altered to improve performance and functionality on my system. And which process may be the best one to alter
Last week my server crashed. I'm trying to diagnose the cause.
This is the relevant error message in /var/log/messages:
Code:
I'm assuming that I can conclude, then, that apache/httpd was the cause of the memory leak?
Next, I've been tracking my memory usage. Using top, this is an average memory load level for my server:
Code:
I'd like to confirm if my understanding of this data is correct, because Plesk indicates that my memory usage is only 50% or less. (Though I have read a number of reports indicating that Plesk's measurements are frequently wrong.)
Top says: Of the 2,073,156K total memory, 1,982,572K (95.63%) is being used, 90,584K (4.37%) is free. Of that sum, 421,948K (20.35%) are being used as buffers. Additionally, of the 2,096,472K of Swap, 60K is used, and 887,700K (42.34%) is cached.
My questions: Is my memory actually being 95% used? Or is the buffered quantity (20.35%) not a use of physical/virtual memory? (i.e. is it disk usage?) Does the amount of cached Swap influence the percentage of physical/virtual memory being used?
In other words, who is correct? Plesk says I'm using 40-50% of my memory, whereas top says 85-95%.
There is a computer with two "Xeon(R) CPU X5550 @ 2.67GHz" CPU. The Hyper-threading is enabled, so it looks like 16-core system, but really there is only 8 physical cores.
I know that when hyperthreading is enabled, each physical core is splitted into two virtual cores. I want to know, which pair of virtual cores shares a physical core and which are not. Or, how (in what order) will Linux enumerate HT-cores comparing to real cores. (enumerating is done for sched_setaffinity and taskset masks).
I have a dump of /proc/cpuinfo file from the system.
I think there are possible:
CPU0-CPU7 are not sharing phys. core. CPU8-CPU15 too. But sharing is in pairs CPU0+CPU8, CPU(i)+CPU(i+8) and so on. or CPU0+CPU1 are from single physical, CPU2+CPU3, CPU(2*i)+CPU(2*i+1). or exotic CPU0+CPU15 sharing, CPU1+CPU14 ... or random?
The hard moment in this case is that there are 2 physical dies of CPU (two sockets), and usual recommendation of using "physical id:" field can't help
The cpuinfo:
processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 26 model name : Intel(R) Xeon(R) CPU X5550 @ 2.67GHz
To get the kernel messages of new java process, i refer the details from /proc/<java pid>/stat and /proc/<java pid>/statm files. For some java processes, I didn't find any details in the /proc/<java pid>/statm file. It has only 7 number of 0s. But /proc/<java pid>/stat file has the details. And also this kind of process will have the life time of nearly 1 minute.
Kernel version using: Linux-2.6.18-8.1.8.el5 Is there any possibility of java process without the memory details in the /proc/<java pid>/statm file? If it is possible, how to know the memory related details of that processes?
Some of our workstations have LTO's attached and they seem to drop off every now and again, the only thing which picks them up again (besides a reboot) is the famous rescan-scsi-bus script from here
The thing is that I'd like non-root users to be able to run this script, which in turn needs root to /proc/scsi/scsi
I am trying to use eciadsl in ubuntu 10.10 in order to connect my Prolink H9601 USB ADSL modem(Conexant based) to the internet.eciadsl worked to some extent in ubuntu 9.10 but in ubuntu 10.10 it returns [EciAdsl 1/5] Setting up USB support...
I presume this is because ubuntu 10.10 does not mount USB device filesytem (usbfs) in /proc/bus/usb folder and i can't manually create this folder therefore making it impossible to mount usbfs manually into this folder.