Journalling Flash File System

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1 Introduction
2 Enable JFFS: Create /jffs
3 Options for Increasing JFFS Space
4 Testing ipkg

Introduction

Journalling Flash File System (JFFS/JFFS2) is a re-writable area within a DD-WRT-enabled device.

Located in /jffs.

Contents stored:

On DD-WRT Device main flash directly on the device (/jffs), or
mount --bind /storagelocation /jffs.
Where storagelocation is
- Off-board supplemental flash, see SD/MMC_mod, (/mmc/jffs).
- Network Area Storage [NAS], or Server. (//servername/sharename)
- JFFS reports as it's own free space, the free space on Share or SD Card, in the Web Interface

Examples of the kind of programs and data are:

Custom configuration files
NoCat splash pages and configuration
ipkg (Requires JFFS. See ipkg.)
Web-site hosting
Many other things.
JFFS must be Enabled for certain /jffs-dependent applications.

Enable JFFS: Create /jffs

Prerequisites

To enable JFFS you will need a router with at least 4MB flash, a build that supports JFFS such as the Mini build which is the smallest build to support JFFS thus leaving the most space for the JFFS partition, and your build must leave at least 324KB of flash free for the JFFS file system structure which will not be usable space. v24 pre-SP2 Standard builds no longer leave enough space for JFFS on 4MB devices so use the Mini build or one of Eko's specialty builds.

Very old versions of some Linksys routers (no longer manufactured for many years) contained 8MB of Flash and 32MB of RAM, many DD-WRT-capable devices today contain 4MB of Flash memory; a few models from certain manufacturers contain more flash (La Fonera, ASUS WL-500GP), some contain less (2MB). See Supported Devices.

Note that DD-WRT v24sp1 VPN builds have the JFFS feature removed, presumably due to conflicts that Brainslayer found between JFFS and bandwidth monitoring. See this thread for more information. Users interested in v24sp2 can opt:

Use a build other than VPN, both MINI and MEGA still have JFFS
Use an older build of DD-WRT
Use a custom build, either homemade or dd-wrt.v24-10086_NEWD_openvpn_jffs_small.bin, which is described here as missing "snmp, all languages, some GUI styles and more.".

NOTE FOR ASUS WL500W

As of October 7th, 2009, consider the following or you may BRICK your WL500W router:

Brainslayers mega flash size - 7.33MB
Eko's Big Flash size - 5.9MB

Now, the error only occurs when JFFS2 is enabled and the router reboots, so you are safe if you DONT enable JFFS2.

Total available JFFS2 size for BS's build is 640KB which overwhelms the kernel and causes a panic. Even using a storage device with the command mount -o bind /mnt/jffs /jffs will still cause a kernel panic.

Eko's JFFS2 partition size is 1640KB+, allowing much more room.

I tested this on BS's 12996,12874 and 12533 builds and partially bricked my router several times. (A simple power disconnect for 30 secs will allow it to recover)

Eko's build however works flawlessly AND provides the SAME features (except for connection warning) as BS's.

One thing I am still unsure of is why this particular model Asus router is subject to this bug, but in the mean time, I suggest using Eko's Big build until the dev's can work it out..

Flash Wear: A Warning

Take care not to store frequently changing files (i.e. often-changing log files) on Flash as this can cause flash wear-out over time.

A journalling flash file system is specifically designed to minimize frequent overwrites.
Files which are read many times but written infrequently work well on main flash.
Using the space provided by SD/MMC_mod places wear on replaceable secondary flash storage.

Directions for (normal) users: using Web-GUI Interface

The steps to enable JFFS through the router web page are very specific. To avoid having to reset and reprogram your router, it's smart to make a backup here of your settings. If you follow these steps exactly, it should not lock up.

On the router web page click on Administration.
Scroll down until you see JFFS2 Support section.
Click Enable JFFS.
Click Save.
Wait couple seconds, then click Apply.
Wait again. Go back to the Enable JFFS section, and enable Clean JFFS.
Do not click "Save". Click Apply instead.

The router formats the available space.
Wait till you get the web-GUI back, then disable "Clean JFFS" again.
Click "Save".
It may be wise to Reboot the router, just to make sure

If you don't see the Enable JFFS option on your Administration page, it is likely because your router has insufficient flash memory to hold both DD-WRT and a JFFS partition. If you have a 4MB router, you may be able to work around this by using the mini version of DD-WRT

Directions for (freaky) Linux Gurus: CLI

WARNING

A user comments: I tried the following commands under La Fonera firmware v24 RC4 and corrupted all my settings. I had to recover my unit with the procedures on La Fonera flashing page. I am not sure if this is a bug or these commands are not suited for La Fonera. Please try to use the web interface above. It works for me.

Enter the following commands from the CLI:

nvram set jffs_mounted=1
nvram set enable_jffs2=1
nvram set sys_enable_jffs2=1
nvram set clean_jffs2=1
nvram set sys_clean_jffs2=1
nvram commit
reboot

Note: Device might reboot/hang after cleaning which might take long; be patient.

To unmount the JFFS:

nvram set sys_enable_jffs2=0
nvram set sys_clean_jffs2=0
nvram set jffs_mounted=0
nvram commit
reboot

Afterwards you can delete these variables with "nvram unset <variable>".

Options for Increasing JFFS Space

Add a 1GB flash memory card

Add the SD/MMC mod
- up to (at least) 1GB storage using common swappable SD memory cards (built-in support with DD-WRT v2.4 and later).
- create the folder /mmc/jffs

mkdir /mmc/jffs

Use the Mount Bind command to point /jffs to the storage card:

mount --bind /mmc/jffs /jffs

with v24 enable JFFS2 support (tab: Administration -> tab: Management -> section: JFFS2 Support)

or command nvram set sys_enable_jffs2=1

To use ipkg also create folder /jffs/tmp/ipkg

mkdir /jffs/tmp

mkdir /jffs/tmp/ipkg

For Windows: WinSCP can be used to transfer files to and from the router, eliminating the need to pull the card out and put it in a card reader on a PC.
For Linux, Mac OS X: Other SCP transfer applications exist.
Removed cards can be accessed natively in Linux or OS X, or on Windows with the Ext2FS driver ([1] or [2]).
On older firmware (v2.3), the limited JFFS space can be used to hold the drivers to load support for the SD card.

Add USB Storage

Routers with USB storage like Linksys WRTSL54GS or ASUS WL-500g Premium can have firmware with built-in USB support and then /jffs mounted on the USB device. To enable USB on these devices see: USB_storage
- V24 and later firmware: USB support is available within Mega and some Mini builds.

Using V24SP1 Mega on an Asus WL-500W with external USB HDD:

To mount the USB drive, and enable /jffs

mount /dev/scsi/host0/bus0/target0/lun0/part1 /mnt
mkdir /mnt/jffs
mount /mnt/jffs /jffs

Also enable JFFS2 support in either web-GUI (tab: Administration -> tab: Management -> section: JFFS2 Support)

or with the command

nvram set sys_enable_jffs2=1

To use ipkg also create folder /jffs/tmp/ipkg

mkdir /jffs/tmp
mkdir /jffs/tmp/ipkg

Using CIFS (Client Samba): Storing /jffs content remotely

One option is to create a share on the network and mount it on the router at /jffs using CIFS. Exact steps at CIFS

Overview:

Enable JFFS in the web-GUI or put the following command in a Script or Startup Command.

nvram set sys_enable_jffs2=1

Create a share on a CIFS-capable server called jffs.
- Standard Microsoft Windows Shared Folder
- Other operating systems may refer to SMB or Samba
In the Web GUI mount the CIFS share at /jffs.
Folder /jffs appears locally, while

Content actually saved remotely, on

NAS (Network Attached Storage)
Server (PC or some type of file server)

To use ipkg also create folder /jffs/tmp/ipkg

mkdir /jffs/tmp

mkdir /jffs/tmp/ipkg

Costs:

! Setting up a NAS or Server only for router maybe not economical.
- Equipment Costs: Requires existing NAS or PC Server
- Electricity Costs: if entire Server is only serving router
Availability Demands: CIFS share must be available
- 24/7, or whenever the DD-WRT Device is on, and
- Storing JFFS Share on quality equipment is required (i.e. Raid, Power Backup)
  - ! Remote storage down means /jffs down, could mean DD-WRT Device down (increases the weak points).
Security Limitations: CIFS is limited to Microsoft's SMB protocol, offering up to only 128-bit security.
- Poor Microsoft Protocol Security is not a problem if the LAN is physically and electronically protected from outside or inside intrusion (i.e. Guards, Guns, Locks, Dogs, Mines, Cameras, Firewalls)
LAN Connection Required: NAS cannot be wirelessly attached to DD-WRT Device.
Hassle: Using Microsoft Windows as the jffs Server
- ! Symbolic links in /jffs may not work.
- ! Rename (mv) commands on the /jffs mount may not work.

Most people only own an (inexpensive) Windows PC. A common Desktop PC does not a 24/7 Server make.

The following non-updated (as of 20080520) examples may be out of date:

CIFS was broken on many builds this update author tried. Although other people have reported it working - It may be a limitation of BusyBox CIFS when using NTLMv2 and 128-bit encryption.
(Mostly) only structural and spelling mistakes were corrected below (20080522)

Use a Startup Script: Example 1

Read how to use Startup Scripts. Then place the following into your startup script to mount the JFFS partition:

umount /jffs #unmounts existing /jffs if existing
mount.cifs //<server's IP>/jffs /jffs -o username=<the username>,password=<the password>
nvram set sys_enable_jffs2=1 # fake-enable JFFS. Enable but do not commit. Makes ipkg think jffs2 is enabled.

NOTE: Username is Guest when hosted on Windows XP & 'Simple File Sharing' is enabled - This is the default on Windows XP Home.

Use Startup Scripts: Example 2

This method uses 2 scripts: The first will be started from /tmp/smbshare & mount the samba share under /jffs and start the other script. The second will be started from /jffs and unmount /tmp/sambashare.

Instructions:

Enable CIFS (see also Jffs_sharing_in_a_Linux_server).
Create a script called "startup.smb.sh" on the share:

#!/bin/sh

#smb settings: same as the settings in the webgui
# change these to mount a different share than the current at /jffs
SMBSHARE=`nvram get samba_share`
SMBUSER=`nvram get samba_user`
SMBPASS=`nvram get samba_password`

#script to start in /jffs once we're done mounting
JFFS_SCRIPT=startup.jffs.sh

#where to log what is happening
export SMBLOG=/tmp/smblog
 
####### ok, here we go... ;) #######
echo "" > $SMBLOG
cd /

#make sure JFFS is unmounted.
echo "umounting /jffs if necessary..." >> $SMBLOG
umount /jffs >> $SMBLOG 2>&1

#mount our smbshare at /jffs
echo "mounting $SMBSHARE at /jffs..." >> $SMBLOG
mount.cifs $SMBSHARE /jffs -o username=$SMBUSER,password=$SMBPASS >> $SMBLOG 2>&1

#hand over startup to the JFFS part
/jffs/$JFFS_SCRIPT & >> $SMBLOG 2>&1

4. create a script called "startup.jffs.sh" on the share:

#!/bin/sh

#wait a sec, just to be sure the smb startup script has quit
sleep 1

#unmount the smbshare, its identical to /jffs now anyway :)
umount /tmp/smbshare

#to enable ipkg, we fake JFFS enabled.
#since theres no commit, this wont actually create a /jffs at Startup.
nvram set sys_enable_jffs2=1

#ready to do specific stuff, like starting services
#or other commands from /jffs

5. in the webinterface, enable CIFS with appropriate share/user/pass settings from step 2.

Enter "startup.smb.sh" as the script

6. Apply Changes
7. reboot

Now you should have the share configured in the web interface mounted at /jffs and should also be able to run 'ipkg' !

NOTE: If you are a Linux newbie, and you have problems with file permissions, look at this

Script files must be saved in UNIX format, not DOS. Windows editors that can do this are UltraEdit. EditPadPro and Crimson Editor, are free.
WinSCP can be used to easily change the execute flags on the scripts.

Use Startup Script: Example 3

This method requires 2 shares available for DD-WRT, but allows you to have 2 different areas of storage for the router. Some might find it useful. It is an amalgamation of the previous 2 methods.

Things you need:

2 writeable shares on an NAS or Server.

Procedure:

1. Enable CIFS
2. Create a shell script in the network share, as follows:

#!/bin/sh
nvram set sys_enable_jffs2=1 # fake-enable JFFS
umount /jffs # unmount /jffs if it exists
mount.cifs //<server's IP>/<jffs share name> /jffs -o username=<your username>,password=<your password>

3. Enter the name of the script in the CIFS-Samba startup script box in the Web Interface.
4. Apply changes.
5. Reboot

As an example network setup:

/tmp/smbshare located in a shared folder on the NAS called ddwrt, which contains scripts (including startup.sh containing the above commands), yet to be installed packages and other static data
/jffs located in a shared folder called jffs, which contains program data for installed packages

Testing ipkg

cd /jffs
mkdir -p /jffs/tmp/ipkg
ipkg update
ipkg list

It is recommended that you reboot the router after running the above commands.

Retrieved from "http://wiki.dd-wrt.com/wiki/index.php/Journalling_Flash_File_System"

Categories: Advanced end user | Advanced tutorials

-== Introduction and Overview ==
+{{languages|Journalling_Flash_File_System}}
-The '''[[Glossary#Journalling Flash File System (JFFS)|Journalling Flash File System]]''' (JFFS/JFFS2) allows you to have a writable Linux File System on a DD-WRT enabled router. JFFS is used to store user programs and data into otherwise inaccessible, read-only flash memory. This allows you to save custom configuration files, run [[Ipkg|ipkg]], host custom Web pages stored on the router and many other things not capable without JFFS.
-Except for early versions of some Linksys routers (no longer available), most routers contain 4MB of total internal Flash memory, a few contain more. See [[Supported_Devices|models]]. When using 4MB models, JFFS is only useful or usable with a Mini version of DD-WRT, which leaves about 700KB of available space in /jffs. Standard DD-WRT takes up the entire 4MB.<br>
+= Introduction =
+'''[[Glossary#Journalling Flash File System (JFFS)|Journalling Flash File System]]''' (JFFS/JFFS2) is a re-writable area within a DD-WRT-enabled device.
-== Enable JFFS when Flash Space is Available (i.e. Mini on 4MB, or >4MB Internal Flash) ==
+* Located in ''/jffs''.
-Note: Take care not to store frequently changed files on Flash as this can cause flash wear out over time. While a journal file system minimizes frequent overwrites, it is not a good idea to store frequently changed files on the main flash memory anyway because of flash wear.
+Contents stored:
+* On DD-WRT Device main flash directly on the device (''/jffs''), or
+* ''mount --bind /storagelocation /jffs''.<br>Where ''storagelocation'' is
+** Off-board supplemental flash, see [[SD/MMC_mod]], (''/mmc/jffs'').
+** Network Area Storage [NAS], or Server. (''//servername/sharename'')
+** JFFS reports as it's own free space, the free space on Share or SD Card, in the Web Interface
-'''For Web Interface Users:'''<br>
+'''Examples of the kind of programs and data are''':
+* Custom configuration files
+* NoCat splash pages and configuration
+* [[Ipkg|ipkg]] (Requires JFFS. See ipkg.)
+* Web-site hosting
+* Many other things.
+* JFFS must be Enabled for certain /jffs-dependent applications.
+= Enable JFFS: Create ''/jffs'' =
+==Prerequisites==
+To enable JFFS you will need a router with at least 4MB flash, a build that supports JFFS such as the Mini build which is the smallest build to support JFFS thus leaving the most space for the JFFS partition, and your build must leave at least 324KB of flash free for the JFFS file system structure which will not be usable space. v24 pre-SP2 Standard builds no longer leave enough space for JFFS on 4MB devices so use the Mini build or one of Eko's specialty builds.
+''Very old versions of some Linksys routers (no longer manufactured for many years) contained 8MB of Flash and 32MB of RAM, many DD-WRT-capable devices today contain 4MB of Flash memory; a few models from certain manufacturers contain more flash (La Fonera, [[ASUS WL-500g Premium|ASUS WL-500GP]]), some contain less (2MB). See [[Supported_Devices|Supported Devices]].<br>
+Note that '''DD-WRT v24sp1 VPN builds have the JFFS feature removed''', presumably due to conflicts that Brainslayer found between JFFS and bandwidth monitoring. See [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=31932&postdays=0&postorder=asc&highlight=jffs+menu&start=0  this thread] for more information. Users interested in v24sp2 can opt:
+# Use a build other than VPN, both MINI and MEGA still have JFFS
+# Use an older build of DD-WRT
+# Use a custom build, either homemade or [http://www.dd-wrt.com/dd-wrtv2/downloads/others/eko/V24_TNG/svn10086/dd-wrt.v24-10086_NEWD_openvpn_jffs_small.bin dd-wrt.v24-10086_NEWD_openvpn_jffs_small.bin], which is described [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=36037&p=200431#200431 here] as missing "snmp, all languages, some GUI styles and more.".
+====NOTE FOR ASUS WL500W====
+As of October 7th, 2009, consider the following or you may BRICK your WL500W router:
+* Brainslayers mega flash size - 7.33MB
+* Eko's Big Flash size - 5.9MB
+Now, the error only occurs when JFFS2 is enabled and the router reboots, so you are safe if you DONT enable JFFS2.
+Total available JFFS2 size for BS's build is 640KB which overwhelms the kernel and causes a panic. Even using a storage device with the command mount -o bind /mnt/jffs /jffs will still cause a kernel panic.
+Eko's JFFS2 partition size is 1640KB+, allowing much more room.
+I tested this on BS's 12996,12874 and 12533 builds and partially bricked my router several times. (A simple power disconnect for 30 secs will allow it to recover)
+Eko's build however works flawlessly AND provides the SAME features (except for connection warning) as BS's.
+One thing I am still unsure of is why this particular model Asus router is subject to this bug, but in the mean time, I suggest using Eko's Big build until the dev's can work it out..
+== Flash Wear: A Warning ==
+Take care not to store frequently changing files (i.e. often-changing log files) on Flash as this can cause flash wear-out over time.
+* A journalling flash file system is specifically designed to minimize frequent overwrites.
+* Files which are read many times but written infrequently work well on main flash.
+* Using the space provided by [[SD/MMC_mod]] places wear on replaceable secondary flash storage.
+== Directions for (normal) users: using Web-GUI Interface==
 ''The steps to enable JFFS through the router web page are very specific. To avoid having to reset and reprogram your router, it's smart to make a backup here of your settings. If you follow these steps exactly, it should not lock up.''
-# On the router web page click on "Administration".
+# On the router web page click on ''Administration''.
-# Scroll down until you see "JFFS2 Support".
+# Scroll down until you see ''JFFS2 Support'' section.
-# Click "Enable JFFS".
+# Click ''Enable JFFS''.
+# Click ''Save''.
+# Wait couple seconds, then click ''Apply''.
+# Wait again. Go back to the ''Enable JFFS'' section, and enable ''Clean JFFS''.
+# '''Do not click "Save".''' Click '''Apply''' instead.<br><br>The router formats the available space.<br><br>
+# Wait till you get the web-GUI back, then disable "Clean JFFS" again.
 # Click "Save".
-# Wait couple seconds, then click "Apply".
+# It may be wise to Reboot the router, just to make sure
-# Wait again. Go back to the "Enable JFFS" option, click "Clean JFFS".
-# '''Do not click "Save".''' Click "Apply" instead.
+If you don't see the Enable JFFS option on your Administration page, it is likely because your router has insufficient flash memory to hold both DD-WRT and a JFFS partition. If you have a 4MB router, you may be able to work around this by using the [[What is DD-WRT?#Broadcom Based Devices|mini]] version of DD-WRT
+==Directions for (freaky) Linux Gurus: CLI==
+'''WARNING'''
-The router formats the available space, which is now shown in the JFFS2 Support box.
+A user comments: I tried the following commands under La Fonera firmware v24 RC4 and corrupted all my settings.  I had to recover my unit with the procedures on La Fonera flashing page.  I am not sure if this is a bug or these commands are not suited for La Fonera.  Please try to use the web interface above. It works for me.
-'''For Linux Gurus:'''<br>
+Enter the following commands from the CLI:
-Enter the following commands (when you're connected via ssh or telnet on a shell):
  nvram set jffs_mounted=1
  reboot
-might reboot/hang after cleaning which might take long, so be patient
-'''WARNING'''
-I tried the previous commands under La Fonera firmware v24 RC4 and corrupted all my settings.  I had to recover my unit with the procedures on La Fonera flashing page.  I am not sure if this is a bug or these commands are not suited for La Fonera.  Please try to use the web interface above. It works for me.
-'''NOTE'''
-On my install of DD-WRT (DD-WRT v23 SP2 (09/15/06) vpn - build 3932 - and also when I tried DD-WRT v24) on a WRT54GS (1.1), I found that after mounting the JFFS, I only had 320kb free. I noticed that the mounted partition was /dev/mtdblock/4. I tried mounting the other three block devices, and found that /dev/mtdblock/1 had 3.7MB.
+Note: Device might reboot/hang after cleaning which might take long; be patient.
-To unmount the JFFS (in case it was too small):
+To unmount the JFFS:
  nvram set sys_enable_jffs2=0
 Afterwards you can delete these variables with "nvram unset <variable>".
-== Enable JFFS when little flash (i.e. Standard firmware on typical Router with only 4MB of Main Flash) ==
+=Options for Increasing JFFS Space=
-=== Add a 1GB flash memory card (more r/w storage directly on the router)===
+== Add a 1GB flash memory card ==
+* Add the [[SD/MMC mod]]
+** up to (at least) 1GB storage using common swappable SD memory cards (built-in support with DD-WRT v2.4 and later).
+** create the folder /mmc/jffs
+::: ''mkdir /mmc/jffs''
+:* Use the Mount Bind command to point /jffs to the storage card:
+::: ''mount --bind /mmc/jffs /jffs''
+:* with v24 enable  JFFS2 support (tab: Administration -> tab: Management -> section: JFFS2 Support)
+:: or command ''nvram set sys_enable_jffs2=1''
+:* To use ipkg also create  folder /jffs/tmp/ipkg
+:::''mkdir /jffs/tmp''
+:::''mkdir /jffs/tmp/ipkg''
+* For Windows: [[WinSCP]] can be used to transfer files to and from the router, eliminating the need to pull the card out and put it in a card reader on a PC.
+* For Linux, Mac OS X: Other SCP transfer applications exist.
+* Removed cards can be accessed natively in Linux or OS X, or on Windows with the Ext2FS driver ([http://www.fs-driver.org] or [http://ext2fsd.sourceforge.net]).
+* On older firmware (v2.3), the limited JFFS space can be used to hold the drivers to load support for the SD card.
-Creating a read-write /jffs space, using little space on the Main internal Flash memory:
-* Add the [[SD/MMC mod]] - up to 1GB storage using common swappable SD memory cards (built-in support in DD-WRT v2.4 and above). Ext2FS driver [[http://www.fs-driver.org]] can be used within Windows 2K/XP to r/w SD cards. [[WinSCP]] can be used to transfer files to and from the router, eliminating the need to pull the card out and put it in a card reader on a PC.
-* On older firmware (v2.3), the limited JFFS space can be used to hold the drivers to load support for the SD card.
+== Add USB Storage ==
+* Routers with USB storage like [[Linksys WRTSL54GS]] or [[ASUS WL-500g Premium]] can have firmware with built-in USB support and then  /jffs mounted on the USB device. To enable USB on these devices see: [[USB_storage]]
+** V24 and later firmware: USB support is available within Mega and some Mini builds.
-* Routers with USB storage: A [[Linksys WRTSL54GS]] or [[ASUS WL-500g Premium]] device has USB capability. Drivers and startup files are stored in a small amount of JFFS space. Any other storage-intensive tasks can then be accomplished on one or more external USB devices.
+*Using V24SP1 Mega on an Asus WL-500W with external USB HDD:
-=== Using Samba/CIFS, General info (additional storage on a NAS or wire-networked computer) ===
+:To mount the USB drive, and enable /jffs
+ mount /dev/scsi/host0/bus0/target0/lun0/part1 /mnt
+ mkdir /mnt/jffs
+ mount /mnt/jffs /jffs
-* One option is to use a CIFS/[[Samba]] share on the network. In the Web GUI mount a [[Samba]] share at /jffs. This creates a read-write directory which is not stored on the router, instead the contents are stored on the Network-Attached Storage (NAS) or computer. The option uses more electricity ($$$ or €€€), but may be useful if you already have a low-power NAS, or an always-on server, when the share is continuously available. Also see [http://wrt-wiki.bsr-clan.de/index.php?title=Jffs this] for more info. To setup your /jffs share to point to a Linux box and you are a Linux newbie [http://wrt-wiki.bsr-clan.de/index.php?title=Jffs_sharing_in_a_Linux_server see this].
+*Also enable JFFS2 support in either web-GUI (tab: Administration -> tab: Management -> section: JFFS2 Support)
+: or with the command
+ nvram set sys_enable_jffs2=1
+*To use ipkg also create  folder /jffs/tmp/ipkg
+ mkdir /jffs/tmp
+ mkdir /jffs/tmp/ipkg
-If you have too little flash memory but need some memory under /jffs you can use [[Samba Filesystem|Samba]] and mount the share under /jffs
+==Using [[CIFS]] (Client Samba): Storing ''/jffs'' content remotely==
+One option is to create a share on the network and mount it on the router at ''/jffs'' using [[CIFS]]. Exact steps at [[CIFS]]
-To mount the samba share under /jffs you can either
+Overview:
-* Use a startup script
+* Enable JFFS in the web-GUI or put the following command in a Script or Startup Command.
-* Use Samba startup scripts
+ nvram set sys_enable_jffs2=1
+* Create a share on a CIFS-capable server called ''jffs''.
+** Standard Microsoft Windows Shared Folder
+** Other operating systems may refer to SMB or Samba
+* In the Web GUI mount the [[CIFS]] share at ''/jffs''.
+* Folder ''/jffs'' appears locally, while
+: Content actually saved remotely, on
+:* NAS (Network Attached Storage)
+:* Server (PC or some type of file server)
+* To use ipkg also create  folder /jffs/tmp/ipkg
+::''mkdir /jffs/tmp''
+::''mkdir /jffs/tmp/ipkg''
+'''Costs:'''
+* ! Setting up a NAS or Server only for router maybe not economical.
+** Equipment Costs: Requires existing NAS or PC Server
+** Electricity Costs: if entire Server is only serving router
+* Availability Demands: CIFS share must be available
+** 24/7, or whenever the DD-WRT Device is on, and
+** Storing JFFS Share on quality equipment is required (i.e. Raid, Power Backup)
+*** ! Remote storage down means /jffs down, could mean DD-WRT Device down (increases the weak points).
+* Security Limitations: CIFS is limited to Microsoft's SMB protocol, offering up to only 128-bit security.
+** Poor Microsoft Protocol Security is not a problem if the LAN is physically and electronically protected from outside or inside intrusion (i.e. Guards, Guns, Locks, Dogs, Mines, Cameras, Firewalls)
+* LAN Connection Required: NAS cannot be wirelessly attached to DD-WRT Device.
+* Hassle: Using Microsoft Windows as the ''jffs'' Server
+** ! Symbolic links in ''/jffs'' may not work.
+** ! Rename (mv) commands on the ''/jffs'' mount may not work.
-NOTE 2: You might not be able to use symbolic links when using windows-hosts. Rename(mv) could work.
+'''Most people only own an (inexpensive) Windows PC. A common Desktop PC does not a 24/7 Server make.'''
-====Use a Startup Script to Samba Example 1====
-Read first, howto use [[Startup Scripts]]. Then place the following into your startup script to mount the JFFS partition:
- umount /jffs
+'''The following non-updated (as of 20080520) examples may be out of date:'''
- smbmount //<server's IP>/jffs /jffs -o username=<your username>,password=<your password>
+* CIFS was broken on many builds this update author tried. Although other people have reported it working - It may be a limitation of ''BusyBox'' CIFS when using NTLMv2 and 128-bit encryption.
+* (Mostly) only structural and spelling mistakes were corrected below (20080522)
-*NOTE: username is guest if hosted on Windows XP & 'Simple File Sharing' is enabled.
+===Use a Startup Script: Example 1===
+# Read how to use [[Startup Scripts]]. Then place the following into your startup script to mount the JFFS partition:
-==== Use Samba Startup Scripts 2====
+ umount /jffs #unmounts existing /jffs if existing
-This method uses 2 scripts: The first will be started from /tmp/smbshare, mount the samba share under /jffs and start the other script. The second will be started from /jffs and unmount /tmp/sambashare.
+ mount.cifs //<server's IP>/jffs /jffs -o username=<the username>,password=<the password>
+ nvram set sys_enable_jffs2=1 # fake-enable JFFS. Enable but do not commit. Makes ipkg think jffs2 is enabled.
-Now here are instruction on how to do so:
+NOTE: Username is ''Guest'' when hosted on Windows XP & 'Simple File Sharing' is enabled - This is the default on Windows XP Home.
-) disable JFFS in the web GUI if you had enabled it<br>
+===Use Startup Scripts: Example 2===
-) enable [[Samba Filesystem|samba]] (see also [[Jffs_sharing_in_a_Linux_server]]).<br>
+This method uses 2 scripts: The first will be started from /tmp/smbshare & mount the samba share under /jffs and start the other script. The second will be started from /jffs and unmount /tmp/sambashare.
+Instructions:
+# Enable [[CIFS]] (see also [[Jffs_sharing_in_a_Linux_server]]).
+# Create a script called "startup.smb.sh" on the share:
-) create a script called "startup.smb.sh" on the share:<br>
  #!/bin/sh
  #where to log what is happening
  export SMBLOG=/tmp/smblog
  ####### ok, here we go... ;) #######
  echo "" > $SMBLOG
  cd /
- #make sure JFFS is unmounted. Its recommended to run without JFFS enabled though.
+ #make sure JFFS is unmounted.
- echo "umounting /jffs if nescessary..." >> $SMBLOG
+ echo "umounting /jffs if necessary..." >> $SMBLOG
  umount /jffs >> $SMBLOG 2>&1
  #mount our smbshare at /jffs
  echo "mounting $SMBSHARE at /jffs..." >> $SMBLOG
- smbmount $SMBSHARE /jffs -o username=$SMBUSER,password=$SMBPASS >> $SMBLOG 2>&1
+ mount.cifs $SMBSHARE /jffs -o username=$SMBUSER,password=$SMBPASS >> $SMBLOG 2>&1
- #smbmount ist not working in v23 SP3, so i changed the line above:
- #mount.cifs $SMBSHARE /jffs -o username=$SMBUSER,password=$SMBPASS >> $SMBLOG 2>&1
  #hand over startup to the JFFS part
  /jffs/$JFFS_SCRIPT & >> $SMBLOG 2>&1
-) create a script called "startup.jffs.sh" on the share:<br>
+. create a script called "startup.jffs.sh" on the share:<br>
  #!/bin/sh
  #to enable ipkg, we fake JFFS enabled.
- #since theres no commit, this wont actually enable JFFS
+ #since theres no commit, this wont actually create a /jffs at Startup.
  nvram set sys_enable_jffs2=1
  #or other commands from /jffs
-) in the webinterface, enable [[Samba]] with appropriate share/user/pass settings from step 2. Enter "startup.smb.sh" as the script<br>
+. in the webinterface, enable [[CIFS]] with appropriate share/user/pass settings from step 2.<br>
-) reboot<br>
+* Enter "startup.smb.sh" as the script<br>
+. Apply Changes<br>
+. reboot<br>
 <br>
 Now you should have the share configured in the web interface mounted at /jffs and should also be able to run 'ipkg' !
 *NOTE: If you are a Linux newbie, and you have problems with file permissions, look at [http://wrt-wiki.bsr-clan.de/index.php?title=Jffs_sharing_in_a_Linux_server this ]
-*BONUS NOTE OF HAPPINESS: You need to save the script files in UNIX format, not DOS. One text editor that can do this is UltraEdit. Or Crimson Editor, which is free :o)
+*Script files must be saved in UNIX format, not DOS. Windows editors that can do this are UltraEdit. EditPadPro and Crimson Editor, are free.
+*[[WinSCP]] can be used to easily change the execute flags on the scripts.
-==== Use Samba Startup Scripts 3 ====
+===Use Startup Script: Example 3 ===
 This method requires 2 shares available for DD-WRT, but allows you to have 2 different areas of storage for the router. Some might find it useful. It is an amalgamation of the previous 2 methods.
 Things you need:
-* 2 writeable shares on another computer/server
+* 2 writeable shares on an NAS or Server.
 Procedure:
-&nbsp;&nbsp;1. Enable JFFS<br />
+. Enable [[CIFS]]<br />
-&nbsp;&nbsp;2. Enable [[Samba]]<br />
+. Create a shell script in the network share, as follows:<br />
-&nbsp;&nbsp;3. Create a shell script in the Samba share, as follows:<br />
  #!/bin/sh
- umount /jffs
+ nvram set sys_enable_jffs2=1 # fake-enable JFFS
- smbmount //<server's IP>/<jffs share name> /jffs -o username=<your username>,password=<your password>
+ umount /jffs # unmount /jffs if it exists
-&nbsp;&nbsp;4. Enter the name of the script in the Samba startup script box in the GUI<br />
+ mount.cifs //<server's IP>/<jffs share name> /jffs -o username=<your username>,password=<your password>
-&nbsp;&nbsp;5. Reboot
-As an example, my DD-WRT has these shares:
+. Enter the name of the script in the CIFS-Samba startup script box in the Web Interface.<br>
+. Apply changes.<br>
+. Reboot
-* '''/tmp/smbshare''' located in a shared folder on my NAS called '''ddwrt''', which contains scripts (including '''startup.sh''' containing the above commands), yet to be installed packages and other static data
+As an example network setup:
-* '''/jffs''' located in a shared folder called '''jffs''', which contains program data for installed packages
-===IPKG Note===
+* '''/tmp/smbshare''' located in a shared folder on the NAS called '''ddwrt''', which contains scripts (including '''startup.sh''' containing the above commands), yet to be installed packages and other static data
-NOTE: Though not using the JFFS partition on the router, you must still have JFFS enabled in order to use ipkg. Disabling jffs also disables ipkg!
+* '''/jffs''' located in a shared folder called '''jffs''', which contains program data for installed packages
-== Testing ==
-Log in to the shell (Telnet or SSH) and run:<br>
+= Testing [[ipkg]]=
+Log in to the CLI (via Telnet or SSH) and enter the following commands:<br>
+ cd /jffs
  mkdir -p /jffs/tmp/ipkg
  ipkg update
  ipkg list
+It is recommended that you reboot the router after running the above commands.
-[[Category:English documentation]]
+[[Category:Advanced end user]]
 [[Category:Advanced tutorials]]