I'm writing to you because I encountered the following problem. My program displayes all network interfaces that are available in the system, but I would like to adda functionality in which a user can enter a destination address IP (ex. the IP address of the Google search engine) and will get information which network interface will be used to send it. As I know it is associated with reading information from routing table in the system. Maybe you know the API (functions/methods) which I could use to do it in RedHat ? I program in C/C++, but if you know how to do it in other programming languages (Java, Perl, Python) I will be grateful for any information.
I am running a test to determine when packet drops occur. I'm using a Spirent TestCenter through a switch (necessary to aggregate Ethernet traffic from 5 ports to one optical link) to a server using a Myricom card.While running my test, if the input rate is below a certain value, ethtool does not report any drop (except dropped_multicast_filtered which is incrementing at a very slow rate). However, tcpdump reports X number of packets "dropped by kernel". Then if I increase the input rate, ethtool reports drops but "ifconfig eth2" does not. In fact, ifconfig doesn't seem to report any packet drops at all. Do they all measure packet drops at different "levels", i.e. ethtool at the NIC level, tcpdump at the kernel level etc?nd am I right to say that in the journey of an incoming packet, the NIC level is the "so-called" first level, then the kernel, then the user application? So any packet drop is likely to happen first at the NIC, then the kernel, then the user application? So if there is no packet drop at the NIC, but packet drop at the kernel, then the bottleneck is not at the NIC?
I have a question regarding packet drops. I am running a test to determine when packet drops occur. I'm using a Spirent TestCenter through a switch (necessary to aggregate Ethernet traffic from 5 ports to one optical link) to a server using a Myricom card. While running my test, if the input rate is below a certain value, ethtool does not report any drop (except dropped_multicast_filtered which is incrementing at a very slow rate). However, tcpdump reports X number of packets "dropped by kernel". Then if I increase the input rate, ethtool reports drops but "ifconfig eth2" does not.
In fact, ifconfig doesn't seem to report any packet drops at all. Do they all measure packet drops at different "levels", i.e. ethtool at the NIC level, tcpdump at the kernel level etc? And am I right to say that in the journey of an incoming packet, the NIC level is the "so-called" first level, then the kernel, then the user application? So any packet drop is likely to happen first at the NIC, then the kernel, then the user application? So if there is no packet drop at the NIC, but packet drop at the kernel, then the bottleneck is not at the NIC?
Centos el5xen x86_64 in a company network, novell-netware, Static IP I have several issues with the Xen network configuration. This configuration worked before, and was maded by a other personn with a higher level in centos and network . I'm trying to re-install xen in bridging mode.
1) The dom0 ping in the company network, but can't acess to the Internet.
I de-activated firewall, iptables and SE-Linux for the test.
the ifconfig-a command return eth0 lo sit0 (IPV6 encapsuled in IPV4) vif0 vnet0 but no Peth0 Physical device
with my other ethernet card problem solved, I suddenly run into this:
Code: eth1 Link encap:Ethernet HWaddr 00:02:e3:16:37:4c inet addr:10.0.2.1 Bcast:10.0.2.255 Mask:255.255.255.0 inet6 addr: fe80::202:e3ff:fe16:374c/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
This card was working perfectly fine up until....an hour ago and it started doing this. My iptables isn't blocking it somehow, because I didn't change anything. I tried reverting to an older kernel and that didn't help. It's not the network cable, it works fine in any other card. Also, the dropped packets seem to count down? It seems to go down by exactly one every time I run ifconfig, no matter the length of time in between running it.
i have encounter strange situation i have set all my network configuration via /etc/sysconfig/network-scripts/ifcfg-eth0 ,eth0.2 ,eth1 etc ....i have used only once Gnome network manage settings to add routing since then all my network config change although all files mention above showing the same config i have set initially and same for Gnome network Manager.
where are the interface configurations (set by ifconfig, not the static ones) stored? I'm asking because I'm trying to understand, more broadly, the order of IP address lookup. If I ping the local machine (localhost, or one of the interfaces) no messages get sent out (at least according to wireshark), so some local lookup must be taking place.
I have a laptop running 11.2 with an internal Broadcom-based Wi-Fi card that's working fine. I'm trying to get 802.11n going with the WUSB600N. The USB ID on this device is 1737:0079. I believe this means it's a "V2" with an RT3572 chip.
No driver loads for this device when it's plugged in. If I do a "modprobe rt2870sta", a driver loads, and syslog shows "rtusb init" and "usbcore: registered new interface driver rt2870". But ifconfig -a doesn't show a new network interface. I've also tried building the RT3572 driver from the manufacturer's web site. It builds fine, and modprobe will load it, but I get the same results as the rt2870sta driver.
I recently installed a new CPU and motherboard in my Media Server, but the ethernet port isn't showing up under ifconfig. Is there any way to install additional drivers? EDIT: The model is Realtek RTL8111/8160B.
i know this is crazy, but im using a [URL] and have loaded a copy of "red hat linux 7" on the computer. i have no idea what kind of hardware config/spec stuff i should have in my immediate vision, and if i did i'm not sure how i would make sense of it all. linux loaded fine. didnt save drivers. eth0 not showing in ifconfig report, but lo is connecting to network, other host cannot ping linux and vice versus
can mount a cdrom, but not a usb flash dont quite understand how the load methods work involving /mnt/cdrom/"usbutils-0.86tar.gz" eth0 problems and gnome rpm stupidity keeps me from upgrading sys from old version to a newer version, cant even find the cmd to show me that info, sorry. have usb files i want to mount, dont know how to loAD THE CDROM FOLES, SO EVEN THAT ISNT WORKING OUT HAVE DISCS WITH howtos just need to stay focused on steps to get desired end result, while trying to learn too much info for what im currently doing between all the f!@#@ing windows i have open.
I'm trying to install a Linux driver for my wireless network card (D-Link DWL-G510) on my Red Hat Linux 7.1 machine with a 188.8.131.52 kernel. I downloaded the serial monkey driver from the sourceforge site and was able to successfully compile the rt73 module and load it into the kernel. The problem now is that everytime I issue the command ifconfig wlan0 up it keeps returning with the following error message: wlan0: unknown interface: No such device.
I'm at a loss as to what to do here. I specifed wlan0 as the alias for the rt73 module in the modules.conf and also tried to load the driver with the command modprobe rt73 ifname=wlan0 (this specifies the interface name according to the instructions packaged in the driver), but the error message still keeps coming up.
Is there something else I need to do in Linux to configure the wlan0 part or is the module not recognizing the wireless network card? It would be quite strange if it is the later since all information from the Internet is indicating this is the linux driver I should be using for mentioned wireless card.
I have ran the installation of Ubuntu (10.10) on my Acer Aspire computer, I chose to wipe the disk and use only linux, however after installing and restarting, I get some sort of terminal/command line and not the actual operating system. I did not install Ubuntu Server and this disk worked on another computer (actually the one I am typing this on right now).
I got a problem with my CentOS server. Somebody told me OpenVPN Requires different changes inside my firewall settings. That could be the problem why openvpn wont load..I receive this error on my CentOS panel when im trying to connect into the centos openvpn (with my winxp pc):
Having one issue with evolution not showing html websites showing up in email like verizon sending a promo. I have gone to edit, preferences, mail preferences, html messages and have always load images from the internet chosen. I have also added sender to contacts. Even if I right click message and tell it to dload images it doesn't.
I want to add a few linux server to our monitoring system (solarwinds).
We have to get this information by snmp.The items we need are: 1-In Byte Transferred on every network interface 2-Out Byte Transferred on every network interface. 3-Memory Usage 4-Memory Free 5-CPU usage 6-Free Disk space on partiotion 7-Uptime
I could not find snmp OID or names for this object to fetch.
I've got a vmware install of Fedora 12 running as a server. This install has the /etc/sysconfig/network-scripts/ifcfg-eth0 file configured with the proper info and the service has been restarted. When I run ifconfig I only get the loopback interface, when I run ifconfig -a I can get the eth0, but without the pre-configured ip address. When I enter ifconfig eth0 up I can activate the interface, but without the afore mentioned ip address. I need to be able to yum ssh, install it, and run it with rsa keys. Can do none of this without an interface obviously.
I am analyzing memory usage on a Linux system. When I run vmstat -s, I see the following:
waffleman@waffle-iron:~$ vmstat -s 3549184 K total memory 3206708 K used memory 1918012 K active memory 1037320 K inactive memory 342476 K free memory
I know the system has 4096 MB of RAM installed, but why does it show only 3466 MB? Can this be interpreted as total "available" memory? Perhaps the missing 630 MB is being used by the kernel and cannot paged out?
I also tried this on on an Embedded Linux system and saw a similar result. The DRAM chip has 128 MB, but only 124 MB shows up in vmstat.
1. Is that WA% only disk I/O or can it include network IO? 2. How do I identify which processes are making up that WA statistic? 3. Why does iostat report 100% utilization when the drive read/write speeds are under 1MB/s?
The reason I'm asking.
My Oracle stats are saying that the drives are running at about 5MB/s right now, the WA is 55%, and the iostat -m -x is reporting the drives running at 100% utilization with a read/write rate under 1MB/s. The read speed of the drive is 98MB/s (tested with hdparm -tT when I installed the drives)
I know I have a few queries using full tables scans which I'm working on but I'd think that 100% utilization should be running at the full 98MB/s.
I want to try to identify which process (most likely and oracle one) is using the 100% utilization/55% WA.
I just installed Fedora 13 from the Live CD. FIrst off I read the guide and the first step doesn't even work for me. System>Administration>Network does not exist. If I go to System then Preferences I see a Network Manager but it looks nothing like what these screen shots look like. [url]
No wireless card show up in the wireless tab of Network Manager. How can I fix this since my card is listed in ifconfig and iwconfig. Wifi card is a Zonet zew2500p