Tagged Questions
0
votes
1answer
54 views
ixgbe: increase rx performance
I have an Intel 82598EB 10GBE NIC.
I need to receive traffic without packet loss.
Data rate is 4-5 Gbps, packet size is 1500-9600 bytes.
I had already configured smb and irq affinity.
I also tried ...
0
votes
1answer
67 views
Enable kernel module for VPN
I'm trying to turn on modules for VPN so I followed this tutorial to compile new ubuntu kernel 3.8.6 .
But the features I've turned on using make menuconfig seem not to be enabled.
(the features I ...
0
votes
2answers
28 views
can't update with this error messg
I got this message:
not enough free disk space.... The upgrade needs a total of 31.8 M
free space on disk '/boot'. Please free at least an additional 31.8 M
of disk space on '/boot'. Empty ...
0
votes
1answer
77 views
How to troubleshoot high kernel time (high network usage; high interrupts)
I've noticed that I have high kernel time when doing a lot of network traffic in Linux. I also noticed that 45% of my CPU is spent doing interrupts. How can I further troubleshoot this?
2
votes
0answers
166 views
Failed to execute shell script from “network” udev rule to change the MAC-address
I am trying to execute a shell script from udev rule, when a network interface is added, as follows:
SUBSYSTEM=="net", ACTION=="add", KERNEL=="eth*", PROGRAM="/usr/local/bin/changemac.sh", ...
2
votes
1answer
172 views
What does “kernel-resident” mean?
Quoting from the ifconfig man page:
ifconfig is used to configure the kernel-resident network
interfaces. It is used at boot time to set up interfaces as necessary.
After that, it is ...
0
votes
0answers
103 views
Unable to boot Xen 4.1.3 with kernel image shared through cifs
I've configured xen 4.1.3 with CentOS 6.3 and kernel version 3.5.3. I've vm images to my network shares over cifs. cifs is mounted and i can access it from my Dom0 but when try to boot vm using the ...
1
vote
2answers
586 views
SCTP support for Linux kernel 3.3.4-5.fc17.x86_64
I'm using Fedora 17 64-bit version, with Linux kernel version 3.3.4-5.fc17.x86_64.
I installed lksctp using yum.
sudo yum install lksctp-tools.x86_64
When I try to run
sctp_status -H 127.0.0.1 ...
2
votes
2answers
255 views
SIOCSIFADDR: File exists after upgrading kernel
Since upgrading my (Gentoo) kernel from 2.6.38 to 3.3.8 (via oldconfig), I can't get the network on eth0 up anymore. It reports "SIOCSIFADDR: File exists" with a number of other SIOCSIF* errors that ...
0
votes
1answer
462 views
How to calculate TCP checksum [closed]
I am using netfilter hook POST_ROUTING in a kernel module to capture packets.
I am doing NOTHING to the packets, not a single change.
I simply check if it's a TCP and then re-calculate the ...
4
votes
1answer
509 views
How can I use netconsole to help solve a kernel panic?
When I try to use a raid as root, my system panics.
I want to read the kernel output right before the panic, but can't scroll up.
After Googling a bit, I wanted to try netconsole.
but I get no output ...
4
votes
2answers
709 views
How to know if a network interface is tap, tun, bridge or physical?
As far as i know, there are 4 main types of network interfaces in linux: tun, tap, bridge and physical.
When i'm doing sys admin on machines running KVM, i usually come accross tap, bridge and ...
1
vote
1answer
258 views
Wireless not showing a network in the scan results
I have a weird problem of connecting to a wireless network. I am connecting to a network named "C-202" with WPA-Personal. This network shows up in the scan results some time and won't show some time. ...
3
votes
1answer
1k views
Debian 6.0 system with 2.6.39 kernel dropping packets, sandy bridge hardware
I recently migrated an existing Debian system to new hardware, a core i3 chip running on an intel sandy bridge motherboard. I’m experiencing a very strange problem; when I ping my router, about 50% of ...
2
votes
2answers
238 views
UDP multicasting broken after kernel update
I've got an embedded system which is running a stripped down Gentoo userland with a manually build kernel. The system acquires data from a PCI card and sends it out to an UDP multicast group.
All ...
7
votes
1answer
3k views
Buffer size for capturing packets in kernel space?
Going through the man page of tcpdump, it seems kernel can drop the packets if the buffer is full. I was wondering if:
that size is configurable and/or
where can I see the size for my distro?
From ...
14
votes
2answers
5k views
how to check rx ring, max_backlog, and max_syn_backlog size
Quite often in the course of troubleshooting and tuning things I find myself thinking about the following Linux kernel settings:
net.core.netdev_max_backlog
net.ipv4.tcp_max_syn_backlog
...
4
votes
1answer
259 views
NetBSD 5.1 NDIS Kernel Compile Error
I have an old Toshiba Satellite 4015CDT, with Pentium II MMX, 32MB RAM, 4GB HDD. It also has one USB 1.0 port, parallel and serial ports, a 3.5" floppy drive and a CD-ROM drive (almost dead). I've ...
2
votes
2answers
728 views
no network device found after Kernel update
So I managed to install Debian 5 on an eBox 3300MX (an embedded type computer). I added a custom kernel after getting a basic install done. That was to get the network card to work. After that, I ...
4
votes
1answer
2k views
What is the loopback interface
What is the loopback interface and how does it differ from the eth0 interface?
And why do I need to use it when mounting an ISO or running a service on localhost?
