My internet over usb used to just work on my BBB but now every time I boot I have to manually add
route add default gw 192.168.7.1
echo "nameserver 8.8.8.8" >> /etc/resolv.conf
I as following this guide but in /opt/scripts/boot/am335x_evm.sh
I can no longer find
/sbin/ifconfig usb0 192.168.7.2 netmask 255.255.255.252
/usr/sbin/udhcpd -S /etc/udhcpd.conf`
so I can add /sbin/route add default gw 192.168.7.1 metric 1
Where can I add this line?
edit: Host computer is windows 10.
The kernel maintainers update the kernel for that chip-family daily, so you should git pull that /opt directory you mentioned and then run the ./kernel_update in /opt/path/to/tools.
All of the directories on the BBB that can be updated in this manner are on https://github.com/RobertCNelson.
ps. I also updated my device tree files.
Related
I was wondering if Docker Swarm was possible to be a load balancer with GlusterFS as the local filesystem? And use Pacemaker to hold the VIP (because I understand Docker cannot create a VIP).
My idea - which I'm hoping can be verified or suggested better :)
System:
2x CentOS 8 servers
- 192.168.0.1
---- /dev/sda (OS)
---- /dev/sdb (data)
- 192.168.0.2
---- /dev/sda (OS)
---- /dev/sdb (data)
Install Pacemaker, Corosync
dnf --enablerepo=HighAvailability -y install pacemaker pcs psmisc policycoreutils-python-utils
systemctl start pcsd
Add a VIP to both servers
pcs resource create vip IPaddr2 ip=192.168.0.100 cidr_netmask=24 op monitor interval=30s
Set up both storage
mkfs.xfs /dev/sdb
Make the directory and add to startup
mkdir -p /my-data/
echo "/dev/sdb /my-data xfs defaults 0 0" >> /etc/fstab
Install GlusterFS on both nodes
dnf install -y glusterfs-server
Setup Gluster for the volume
gluster volume create gfs replica 2 transport tcp node01:/my-data node02:/my-data force
gluster volume start gfs
Make it accessible for the replication
echo 'node01:/my-data /mnt glusterfs defaults,_netdev 0 0' >> /etc/fstab
echo 'node02:/my-data /mnt glusterfs defaults,_netdev 0 0' >> /etc/fstab
Install Docker and Docker-Compose
Initialise Swarm
- on node01 use IP 192.168.0.1 -> manager
- on node02 use IP 192.168.0.2 -> manager
Create the directories
mkdir /mnt/html
mkdir /mnt/mysql
In the docker-compose.yml file:
volumes:
- "/mnt/html:/var/www/html/wp-content"
volumes:
- "/mnt/mysql:/var/lib/mysql"
Apart of the docker-compose.yml - apache:
Use IP 192.168.0.100 as the access on 80
My thoughts are that as 192.168.0.100 is only accessible on one of the Pacemaker resources, that the secondary Manager wouldn't be hit on the front end. If that node went down on the IP .100 then the other node02 would take that IP and the Swarm would still be active.
Is this something that would work? I cant find anything about having a VIP on the Swarm - at least working solutions.
I have them both as Managers because I assume if the manager goes off then its not going to work? Then if I had a 3rd, 4th, etc. I'd add them as Workers.
http://pktgen.readthedocs.org/en/latest/running.html
This is the pktgen dpdk application. The screenshot in that link shows how ports are configured. But For me it doesnt configure at all. I am looking for help as a beginner
First, as you may know, pktgen is an application that use the DPKD framework, thus, you should have bind at least one NIC to DPDK. Check the documentation about DPDK: DPDK building instructions. You should see your NIC correctly bound with this command:
# path/to/DPDK/tools/dpdk_nic_bind.py --status
Then, you can run pktgen. The ports you want to use are specified with the -p option (It's a specific pktgen option so it's after the --). It's a port mask, so for instance, if you want only the first port (port 0) you can use -p 0x1.
Then, the -m option permit you to choose which core will handle which DPDK port. The syntax is not really obvious, I suggest you to read the doc of pktgen about this option: pktgen command line options.
For example, to be short, the option -m "[1:3].0" says you want that CPU core 1 handle "RX port 0", and CPU core 3 handle "TX port 0".
A simple command line for pktgen, if you use only one port running on two cores could be:
./app/pktgen -c 0x7 -n 3 -- -p 0x1 -P -m "[1:2].0"
In that case CPU core 1 and 2 (possible because of the "-c 0x7 option") will be used to handle respectively RX and TX of port 0 (configured with "-p 0x1"). Note that -P is for promiscuous mode.
I'm using iperf3 that is supposedly a rewritten version of iperf. Reason why Im using this is because I love iperf when it comes to TCP and UDP throughput and I now want to test SCTP throughput between my end-points.
However when I'm trying to use the --sctp command that I've seen people been using it says command not recognizable. Is it the implementation I'm using that have not implemented this command?
https://github.com/esnet/iperf
This is the implementation I'm using, can't find any obvious documentation of the SCTP commands related to this. Most SCTP iperf implementations are added manually in the tests and the source code is often not provided.
Any help would be appreciated!
Get a copy of iperf which supports lksctp module of linux kernel. Install it using the standard process. (If it fails, please inform with the error message and the operating system and kernel details). Now to use SCTP in iperf these are the proper syntaxes.
For creating an SCTP server,
iperf -z -s
(-z is for selecting the SCTP protocol and -s is for server.)
For creating an SCTP client,
iperf -z -c <host address> -t <time duration for the connection in second>s -i <interval of the time to print the bandwidth in terminal in second>s
(-z for SCTP, -c is for client. Host address should be the ip address of the server where iperf -z -s is already running. -t is to specify the communication time duration. -i is to specify the interval to show the bandwidth.)
Example:
iperf -z -c 0.0.0.0 -t 10s -i 2s
Here the communication time is 10 seconds and it'll report the bandwidth for each 2 seconds interval.
P.S.
(1) To use iperf for SCTP, you must enable the SCTP module in the kernel and recompile it. The kernel version must be 2.6 or above. Check it using uname -a or uname -r. If you have a lower one, then download a new kernel from The Linux Kernel Archives. And compile it by enabling SCTP.
First check if it is already enabled or not by running these two commands in the terminal.
modprobe sctp
lsmod | grep sctp If you get any output then SCTP is already enabled.
(2) If still iperf with -z fails. Try the following solution. If the two machines are 'A' and 'B'.
First make 'A' the server and 'B' the client. It won't succeed. So
exit by using `ctrl + z` and kill iperf
using `pkill -9 iperf`.
Then make 'B' the server and 'A' the client. It may succeed. If it fails again, kill iperf using the above command and repeat step 1 again. it might get succeeded.
(The 2nd solution works for me with fedora 20 and kernel 2.6 and above.)
Couldn't find any recent answers through googling so I though I would leave an answer here for those looking to installing Iperf3 to use SCTP on RHEL / CentOS.
You'll need to install lksctp-tools-devel first and build from source to enable the SCTP support. Yum Install Iperf3 3.17 with lksctp-tools-devel did not enable SCTP for me.
Currently I am transporting files back and forth over telnet and I would like to send multiple files at once.
However, my target platform (a Blackfin processor) does not have "tar" enabled in its kernel/busybox configuration (a uClinux distribution).
As you all know the normal command is:
nc -p 12345 -l | tar -x
tar -c * | nc 192.168.0.100 12345 # with x.100 the robot IP address
How can I send multiple files using netcat without using tar?
Please, consider that I cannot easily add binaries on the platform. It would be best to do it with basic utilities and/or shell scripts.
Finally managed myself to do this, it can be done!
Here $l> stands for your machine with IP 192.168.0.10. And $e> is done on the embedded device without tar, in my case a robot. It uses old-fashioned dd which is able to copy an entire disk.
$l> nc -p 12345 -l | dd obs=4K of=/tmp/file.jffs2
$e> dd ibs=4K if=/dev/mtdblock2 | nc 192.168.0.10 12345
This is it, but because not everybody knows how to read a filesystem that is in this form, this is how you mount it:
file /tmp/file.jffs2
/tmp/file.jffs2: Linux jffs2 filesystem data little endian
sudo su #careful
mknod /tmp/mtdblock0 b 31 0
modprobe loop
losetup /dev/loop0 /tmp/file.jffs2
modprobe mtdblock
modprobe block2mtd
echo "/dev/loop0,128KiB" > /sys/module/block2mtd/parameters/block2mtd
modprobe jffs2
mkdir /media/robot
mount -t jffs2 /tmp/mtdblock0 /media/robot
Ctrl-D #back as normal user
And yes, you need the loopback device, or else:
sudo mount -t jffs2 /tmp/file.jffs2 /media/robot
mount: /tmp/file.jffs2 is not a block device (maybe try `-o loop'?)
Logically, it is a file (chars), and not a block device. The only thing I do not know is if there is a syntax for dd in which the command on the embedded device, can only select a subset of the filesystem to be included. I don't think this is likely because that would require dd to understand jffs2 while its strength is its raw byte copying behaviour.
I'm trying to make use of the LVM2 functionality in linux (Centos6.0).
When trying to make the first step of defining a PV on a specific block device, I get the following error message:
[root#localhost /] pvcreate /dev/sdb
Can't open /dev/sdb exclusively. Mounted filesystem?
/dev/sdb is not mounted and its partition table was deleted.
I should mention also that /dev/sdb used to represent a larger block device (about 4 times larger) and was reduced by configuration of hardware raid (I split the hd to 4 in the raid controller).
Has anyone ever encountered this error before and knows how to take it from here?
Maybe device-mapper is 'stealing' this device. Try this:
[root#host ~]# dmsetup ls
sdb (253, 2)
VolGroup00-LogVol01 (253, 1)
VolGroup00-LogVol00 (253, 0)
If you find sdb device listed as above example, remove it using dmsetup and create the physical volume:
[root#host ~]# dmsetup remove sdb
[root#host ~]# pvcreate /dev/sdb
Physical volume "/dev/sdb" successfully created
[root#localhost /] pvcreate -vvvvv /dev/sdb
Could ouput more details.
and you could use lsof -L to check if the block device is opened by other process.