Connecting USB hub and flash stick.
Best instructional website:
http://h-wrt.com/

opkg update
opkg install kmod-usb2 kmod-usb-core kmod-usb-ohci 
opkg install nano
opkg install kmod-usb-storage kmod-fs-ext3 block-extroot e2fsprogs fdisk 
opkg install swap-utils

/etc/opkg update is where opkg gets version



Some packages I did not found not necessary, from a link
http://www.tolaris.com/2010/09/01/openwrt-10-03-on-buffalo-wzr-hp-g300nh/

opkg install kmod-fs-btrfs kmod-fs-ext2 kmod-fs-ext3 kmod-fs-ext4 kmod-fs-isofs kmod-fs-reiserfs kmod-fs-vfat kmod-fs-xfs
opkg install kmod-nls-cp1250 kmod-nls-cp1251 kmod-nls-cp437 kmod-nls-cp775 kmod-nls-cp850 kmod-nls-cp852 kmod-nls-cp866 kmod-nls-iso8859-1 
opkg install kmod-nls-iso8859-13 kmod-nls-iso8859-15 kmod-nls-iso8859-2 kmod-nls-koi8r kmod-nls-utf8
opkg install kmod-usb2 kmod-usb-storage kmod-usb-storage-extras block-hotplug block-mount hotplug2




-------------------------------------
Partitioning Flash stick
http://h-wrt.com/en/doc/flash

fdisk make 2 partitionds sda1 is swap and sda2 big one
fdisk -l   shows partitions
fdisk /dev/sda
d delete
n new

p 1  +100M  will be swap 
p 2  rest  

p display what was made
t 1 82 swap creates
p display what was made

w finalize

now we do formating:  
mkswap /dev/sda1
mkfs.ext3 -L RootFS /dev/sda2
----------------------------------------


System needs to be told to use flash as space for root and swap
Edit fstab with text below
nano /etc/config/fstab
------------------------------
config global automount
option from_fstab 1
option anon_mount 1
config global autoswap
option from_fstab 1
option anon_swap 0

config mount
option target /
option device /dev/sda2
option fstype ext3
option options rw,sync
option enabled 1
option is_rootfs 1

config swap
option device /dev/sda1
option enabled 1 
------------------------------





Copy rootfs to usb stick

mount -t ext3 /dev/sda2 /mnt

tar cvO -C / dev/ bin/ etc/ root/ lib/ sbin/ usr/ www/ var/ | tar x -C /mnt
tar cvO -C / sys/ | tar x -C /mnt
tar cvO -C / overlay/ | tar x -C /mnt
tar cvO -C / rom/ | tar x -C /mnt
tar cvO -C / tmp/ | tar x -C /mnt
tar cvO -C / proc/ | tar x -C /mnt
It is split in several lines as some copy operations hang. But it is still fine. 

Reboot

Check if swap is made by issuing command
free
              total         used         free       shared      buffers
  Mem:        29484        14528        14956            0          648
 Swap:       247896            0       247896
Total:       277380        14528       262852


This shows disk space.
df -h
Filesystem                Size      Used Available Use% Mounted on
/dev/root                 2.1M      2.1M         0 100% /rom
tmpfs                    14.4M     48.0K     14.3M   0% /tmp
tmpfs                   512.0K         0    512.0K   0% /dev
/dev/sda2               464.8M    103.5M    337.3M  23% /overlay
mini_fo:/overlay          2.1M      2.1M         0 100% /

If not as above then run 

swapon /dev/sda1  .This works only one time.  

Need to run command 
/etc/init.d/fstab enable          





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Instructions for USB as rootfs, that I have not tried
http://www.rooot.net/en/geek-stuff/openwrt/36-mount-external-usb-root-partition-openwrt.html


mkdir /mnt/usbstorage -p
uci set fstab.@mount[0].target=/mnt/usbstorage
uci set fstab.@mount[0].device=/dev/sda1
uci set fstab.@mount[0].fstype=auto
uci set fstab.@mount[0].enabled=1
uci set fstab.@mount[0].options=rw,sync,noatime,nodiratime
uci commit fstab
/etc/init.d/fstab enable
/etc/init.d/fstab restart
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