Cirros Image creation

cirros

Base Image:
Edit /lib/cirros/ds/ec2 or /etc/cirros-init/ds-ec2 based on image (MAX_TRIES=5, SLEEP_TIME=2)

v6 support (How dhcpcd was built is not captured here):
scp cirros@10.87.118.117:/sbin/dhcpcd /sbin/
scp cirros@10.87.118.117:/sbin/cirros-dhcpc /sbin/cirros-dhcpc
scp -r cirros@10.87.118.117:/libexec /
      dhcpcd-run-hooks          100% 8436     8.2KB/s   00:00
      10-wpa_supplicant           100% 2866     2.8KB/s   00:00
      30-hostname                 100% 3450     3.4KB/s   00:00
      01-test                     100%  276     0.3KB/s   00:00
      02-dump                     100%  120     0.1KB/s   00:00
      15-timezone                 100%  885     0.9KB/s   00:00
      20-resolv.conf              100% 4562     4.5KB/s   00:00
      50-ntp.conf                 100% 2848     2.8KB/s   00:00
      10-mtu                      100%  957     0.9KB/s   00:00
      29-lookup-hostname          100%  811     0.8KB/s   00:00

Change boot order to bring up dropbear first before dhcpcd. <reduces sshable time by 5 seconds>
mv /etc/rc3.d/S50-dropbear /etc/rc3.d/S39-dropbear (31 sec to 26 sec)

dhcpcd args in cirros-dhcpc file:
dhcpcd -h ${hostname:-"hostname"} -A -q -b -L "$iface"
# Specifying -x option increases the boot time by 10 seconds


Other packages installed for Traffic Image:
SFTP Server:
      Download source and compile with the below args:
      ./configure --disable-libutil --disable-lastlog --disable-utmp --disable-utmpx --disable-wtmp --disable-wtmpx --disable-pututline --disable-pututxline --disable-pam --without-pam --without-stackprotect --without-hardening
      make sftp-server
      Copy sftp-server /lib/x86_64-linux-gnu/libnss_files-2.23.so /lib/x86_64-linux-gnu/libc.so.6 /lib64/ld-linux-x86-64.so.2

To increase image size:
1. qemu-img resize cirros-traffic.qcow2 100M
2. launch the VM
3. execute `/sbin/resize-filesystem /dev/root /run/resize.rootfs /dev/console` inside the cirros VM

Either statically build the reqd packages from source (or)
download the package on ubuntu host and copy the binary and the dependent shared libraries.
For eg:
TcpDump (download the tcpdump deb package and do below):
scp cirros@10.87.118.117:/usr/sbin/tcpdump ./
scp cirros@10.87.118.117:/usr/lib/libpcap.so.1.7.2* ./


scp cirros@10.87.118.117:/usr/sbin/in.tftpd ./
scp cirros@10.87.118.117:/usr/sbin/xinetd ./
scp cirros@10.87.118.117:/usr/sbin/vsftpd ./
scp cirros@10.87.118.117:/usr/sbin/thttpd* ./
scp cirros@10.87.118.117:/sbin/arping ./
scp cirros@10.87.118.117:/etc/init.d/S01logging ./
scp cirros@10.87.118.117:/etc/init.d/S70vsftpd ./
scp cirros@10.87.118.117:/etc/init.d/S90thttpd ./
scp cirros@10.87.118.117:/usr/sbin/xconv.pl ./

To compile Python statically on the Ubuntu host follow the below steps:
  Compiling Python2.7:
    ./configure LDFLAGS="-static" --disable-shared
    make LDFLAGS="-static" LINKFORSHARED=" "
    Apply the workaround - https://github.com/usnistgov/REFPROP-cmake/issues/13
    Content of Setup.local is at https://gist.github.com/smurugap/f8f3ce8b96da33d9ad5c782a4c53ff0e
    
  mkdir -p /usr/local/lib/python2.7
  mkdir -p /usr/local/bin
  scp <srcdir>/python /usr/local/bin/
  scp -r <srcdir>/Lib/* /usr/local/lib/python2.7/
  scp <srcdir>/build/lib.linux-x86_64-2.7/_sysconfigdata.py /usr/local/lib/python2.7/
  chmod -R 777 /usr/local/
  
  To install any dist-packages modules inside cirros:
  * pip install the package on the host
  * copy the contents (directory or .py files) to /usr/local/lib/python2.7/ inside the container