GRML iPXE etboot from HTTP (without NFS)

# downlaod Grml image
wget http://download.grml.org/grml32-small_2013.02.iso -O /tmp/grml32-small_2013.02.iso

# mount image
mount /tmp/grml32-small_2013.02.iso /mnt/ -o loop

# copy Grml files to tftpboot
mkdir /var/lib/tftpboot/live/grml/32-small/
cp /mnt/boot/grml32small/initrd.img /var/lib/tftpboot/live/grml/32-small/
cp /mnt/boot/grml32small/vmlinuz /var/lib/tftpboot/live/grml/32-small/
cp /mnt/live/grml32-small/grml32-small.squashfs /var/lib/tftpboot/live/grml/32-small/

# configure NFS
echo "/var/lib/tftpboot/live/grml/32-small *(ro,no_root_squash,async,no_subtree_check)

sysctl

configure parameter

# determine the maximum size of a shared memory segment
cat /proc/sys/kernel/shmmax
 
# set default shared memory limit for shmmax (16 GB)
echo 17179869184 > /proc/sys/kernel/shmmax
 
# add the following line to /etc/sysctl.conf to make a change permanent
echo "kernel.shmmax=4294967296" >> /etc/sysctl.d/90-shmmax.conf
 
# load parameter
/sbin/sysctl -p /etc/sysctl.d/90-shmmax.conf

reduce swap usage
https://en.wikipedia.org/wiki/Swappiness

OpenStack: Floating IP port forward (in development / experimental)

List floatin IPs

openstack floating ip list
+--------------------------------------+---------------------+------------------+--------------------------------------+--------------------------------------+----------------------------------+
| ID                                   | Floating IP Address | Fixed IP Address | Port                                 | Floating Network                     | Project                          |
+--------------------------------------+---------------------+------------------+--------------------------------------+--------------------------------------+----------------------------------+
| dc049c28-6562-4c37-834b-d3a612d4b580 | 1.2.3.4        | None             | None                                 | 39583230-154f-4b56-a56e-2fd83c9986ce | 1eede1bdc28344f3acf6b48b232e406f |
+--------------------------------------+---------------------+------------------+--------------------------------------+--------------------------------------+----------------------------------+

List VMs

OpenStack: Debug DHCP

Get HIGH lease rate not found

for NODE in $(openstack compute service list --service nova-scheduler -c Host -f value); do
    echo ${NODE}
    ssh ${NODE} cat /var/lib/docker/volumes/kolla_logs/_data/neutron/dnsmasq.log | grep "lease not found" | grep Sep | awk '{print $1, $2}' | uniq -c | awk '$1 > 100 {print}'
    echo
done

Many dhcp requests

Octavia: Allow SSH login to Amphora VM

Allow SSH access

LB_ID=foo-lb01-prod
 
AMPHORA_ID=$(openstack loadbalancer amphora list --loadbalancer ${LB_ID} --role MASTER -c id -f value)
AMPHORA_COMPUTE_ID=$(openstack loadbalancer amphora show ${AMPHORA_ID} -c compute_id -f value)
LB_NETWORK_IP=$(openstack loadbalancer amphora show ${AMPHORA_ID} -c lb_network_ip -f value)
SECURITY_GROUP_ID=$(openstack port list --server ${AMPHORA_COMPUTE_ID} --fixed-ip "ip-address=${LB_NETWORK_IP}" -c security_group_ids -f value)
 
# DEBUG: show ingress tcp rules
openstack security group rule list --ingress --protocol tcp ${SECURITY_GROUP_ID}
openstack security group rule create --protocol tcp --dst-port 22:22 --remote-ip 172.16.0.0/12  ${SECURITY_GROUP_ID}
openstack loadbalancer amphora list --loadbalancer ${LB_ID} -c  lb_network_ip -c role -f value
openstack loadbalancer amphora list --loadbalancer ${LB_ID} -c  lb_network_ip --role MASTER -f value
 
# login to amphora VM from OpenStack control node
ssh local@ctl1-dev.dev.i.example.com
ssh -i ~/.ssh/id_rsa_octavia ubuntu@${AMPHORA_VM_IP}

Manuall SSH access

LineageOS: Samsung Galaxy Note 3

Download LineageOS image
https://download.lineageos.org/hlte

wget https://mirror.selfnet.de/lineageos/full/hlte/20200425/lineage-16.0-20200425-nightly-hlte-signed.zip -P /tmp

Andorid Apps (arm, nano)
https://opengapps.org/?api=9.0&variant=nano

wget https://netix.dl.sourceforge.net/project/opengapps/arm/20200429/open_gapps-arm-9.0-nano-20200429.zip -P /tmp

Compile Heimdall (tested with v1.4.2)

sudo apt-get install -y build-essential cmake zlib1g-dev qt5-default libusb-1.0-0-dev libgl1-mesa-glx libgl1-mesa-dev
 
git clone https://gitlab.com/BenjaminDobell/Heimdall.git /tmp/Heimdall
cd /tmp/Heimdall
mkdir build
cd build
cmake -DCMAKE_BUILD_TYPE=Release ..
make
 
# test
cd bin/
./heimdall version

Boot phone to recovery mode
Vol- + Home + Power

Download recovery file
https://twrp.me/Devices/

LXD with OpenvSwitch network

# create bridge
ovs-vsctl add-br mybridge
# ifconfig mybridge up
ip link set mybridge up
ovs-vsctl show
 
# connect ovs bridge to external network
ovs-vsctl add-port mybridge eno1
ifconfig eno1 0
dhclient mybridge -v
ip a show mybridge
route -n
 
# create LXD container
lxc profile create disk-only
lxc storage create pool1 dir
lxc profile device add disk-only root disk path=/ pool=pool1
lxc profile show disk-only
lxc launch ubuntu:18.04 ovs1 -p disk-only
lxc config device add ovs1 eth0 nic nictype=bridged parent=mybridge host_name=vport11
lxc launch ubuntu:18.04 ovs2 -p disk-only
lxc config device add ovs2 eth0 nic nictype=bridged parent=mybridge host_name=vport12
lxc network list

LXD: Network

Configure default profile

lxc network create lxdbr0
lxc profile device add default eth0 nic nictype=bridged parent=lxdbr0

Configure static IP address

lxc stop c1
lxc network attach lxdbr0 c1 eth0 eth0
lxc config device set c1 eth0 ipv4.address 10.0.0.12
lxc start c1
 
# add NICs
lxc config device add vm-dhcp1-dev dev-mgmt-new nic name=dev-mgmt nictype=macvlan parent=dev-mgmt

ipv6

lxc network set lxdbr0 ipv6.dhcp.stateful true

ovs network

lxc profile create disk-only
lxc storage create pool1 dir
lxc profile device add disk-only root disk path=/ pool=pool1
lxc profile show disk-only
lxc launch ubuntu:18.04 ovs1 -p disk-only
lxc config device add ovs1 eth0 nic nictype=bridged parent=ovsbridge host_name=vport11
lxc network list
# test static ip
lxc launch redis r
lxc config device override r
lxc config device set r eth0 ipv4.address 10.100.0.100

Links
https://stgraber.org/2016/03/15/lxd-2-0-installing-and-configuring-lxd-212/
https://thomas-leister.de/en/container-overlay-network-openvswitch-linux/
https://stgraber.org/2016/10/27/network-management-with-lxd-2-3/