20110529
Canon Rebel Xt and 32GB CF
Just thought I'd mention that I've been using a 32GB CF card with no special formatting in the Canon Rebel Xt. It has been working great for years.
20110202
How to run something other than login on a tty
Sometimes you don't want to run login on the console or other terminal. The reasons for this vary. Some appliances want to boot to a shell prompt on the console for debugging purposes (this console typically isn't exposed, so no security problems there). Sometimes you want to use init's restart feature to keep critical daemons alive. I've developed several control and measurement applications that used this feature. Sometimes your want to offer a menu driven interface to your users instead of a cli-based one.
Recently, I had to add support for a menu console to FreeNAS. I couldn't find any immediately available documentation on how-to do this, I had to dive into some little-configured recesses of FreeBSD to make this happen. Thankfully, no code changes to FreeBSD were required to make this work. I thought I'd do a quick how-to here to cover the basics.
We'll start with /etc/ttys. This is the file that has entries like the following:
which tells init to run getty with the parameter Pc on /dev/ttyv0 with TERM set to cons25. Getty is a program, for those that don't know, that sets up the tty device for interactive use so that normal interaction works as you'd expect. While one can run programs without getty, especially on a 'device' that doesn't exist, I'll ignore that path for this post. This is about creating an interactive program that runs on a tty device.
The 'Pc' here is the key to understanding what getty is doing. Pc refers to the gettytab entry 'Pc' which looks something like:
which, according to the gettytab(5) man page means "Use 115200 baud, no parity, hard tabs". This is great if you want to run login to get an account and password, but what if you want to run a program other than login instead? Maybe one that doesn't know about tty sessions, stdin/stdout redirection etc?
The answer turns out to be fairly straight forward. You just tell tty to use a different entry. This scales well for a small number of programs, but not so well if you have dozens since you can't pass parameters to the final program. For my case, I just needed a menu for FreeNAS. I added the following entry:
to /etc/gettytab. This tells getty to run /etc/netcli.sh as root. Since netcli.sh was mucking with the network it had to run as root, but there's no reason it couldn't run as a different user for safety. Once I had this entry in gettytab, I changed the above /etc/ttys line to look like:
and sent init a hup with a "kill -1 1" command (the -1 is very important, otherwise you reboot your system). Once init reparsed /etc/ttys, netcli.sh started running.
Normally, that would be the end of it. However, in this case netcli really is a pyhton script. Why did I have to wrap it in a shell script that looks like:
When you run out of getty, you have a very restrictive shell. The python script called a bunch of other programs, so it needed to have a good path. Also, since the shell didn't need to stick around, I tossed the typical 'exec' at the end of it to save a little bit of memory on this embedded system.
And there you have it. All the steps to create a program that runs automatically at boot. If you have any other cool tricks, please feel free to comment here...
Recently, I had to add support for a menu console to FreeNAS. I couldn't find any immediately available documentation on how-to do this, I had to dive into some little-configured recesses of FreeBSD to make this happen. Thankfully, no code changes to FreeBSD were required to make this work. I thought I'd do a quick how-to here to cover the basics.
We'll start with /etc/ttys. This is the file that has entries like the following:
ttyv0 "/usr/libexec/getty Pc" cons25 on secure
which tells init to run getty with the parameter Pc on /dev/ttyv0 with TERM set to cons25. Getty is a program, for those that don't know, that sets up the tty device for interactive use so that normal interaction works as you'd expect. While one can run programs without getty, especially on a 'device' that doesn't exist, I'll ignore that path for this post. This is about creating an interactive program that runs on a tty device.
The 'Pc' here is the key to understanding what getty is doing. Pc refers to the gettytab entry 'Pc' which looks something like:
P|Pc|Pc console:\
:ht:np:sp#115200:
which, according to the gettytab(5) man page means "Use 115200 baud, no parity, hard tabs". This is great if you want to run login to get an account and password, but what if you want to run a program other than login instead? Maybe one that doesn't know about tty sessions, stdin/stdout redirection etc?
The answer turns out to be fairly straight forward. You just tell tty to use a different entry. This scales well for a small number of programs, but not so well if you have dozens since you can't pass parameters to the final program. For my case, I just needed a menu for FreeNAS. I added the following entry:
#
# FreeNAS menu system entry
#
FreeNAS|freenas|FreeNAS Menu:\
:ht:np:sp#15200:lo=/etc/netcli.sh:al=root:
to /etc/gettytab. This tells getty to run /etc/netcli.sh as root. Since netcli.sh was mucking with the network it had to run as root, but there's no reason it couldn't run as a different user for safety. Once I had this entry in gettytab, I changed the above /etc/ttys line to look like:
ttyv0 "/usr/libexec/getty freenas" cons25 on secure
and sent init a hup with a "kill -1 1" command (the -1 is very important, otherwise you reboot your system). Once init reparsed /etc/ttys, netcli.sh started running.
Normally, that would be the end of it. However, in this case netcli really is a pyhton script. Why did I have to wrap it in a shell script that looks like:
#!/bin/sh
# Helper script to set the path for netcli menu
export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin
exec /etc/netcli
When you run out of getty, you have a very restrictive shell. The python script called a bunch of other programs, so it needed to have a good path. Also, since the shell didn't need to stick around, I tossed the typical 'exec' at the end of it to save a little bit of memory on this embedded system.
And there you have it. All the steps to create a program that runs automatically at boot. If you have any other cool tricks, please feel free to comment here...
20110117
FreeBSD/mips for Cavium Octeon
I've recently improved the ABI selection in FreeBSD/mips. Now it is all handled via MACHINE_ARCH or TARGET_ARCH. mipsel and mipseb are the o32 32-bit versions. mips64eb and mips64el are for n64 64-bit versions.
I've knocked together a script for building an image for the Cavium Octeon eval boards that have CF that can boot using uboot from SDK 1.9.0 and 2.0.0 (and likely earlier versions, but I've not tested them). It creates two partitions: a FAT partition for the kernel and BSD partition for the rest of FreeBSD. It also takes care of building a big endian ufs system on a little endian system. You can find the script here. I've also create an image as well you can grab here. The script contains instructions for how to create the CF image.
Enjoy
I've knocked together a script for building an image for the Cavium Octeon eval boards that have CF that can boot using uboot from SDK 1.9.0 and 2.0.0 (and likely earlier versions, but I've not tested them). It creates two partitions: a FAT partition for the kernel and BSD partition for the rest of FreeBSD. It also takes care of building a big endian ufs system on a little endian system. You can find the script here. I've also create an image as well you can grab here. The script contains instructions for how to create the CF image.
Enjoy
20101202
New FreeNAS beta snapshot released (r5648)
We've released the next beta snapshot of FreeNAS.
You can download the latest from sourceforge.
You can read the release notes for all the details.
Here's a highlight of the issues that we've fixed since the last beta (r5606):
- Upgrades from prior FreeNAS 8 beta releases are now supported.
- zfs creation failures have been fixed. The gui would indicate it succeeded, but you couldn't share it.
- ufs creation failures have been fixed.
- booting off USB or SCSI cdrom is now supported.
- Many disk initialization errors that showed up as odd failures have been corrected.
- lagg has been introduced.
- Errors in the network screen have been corrected.
- The storage wizard no longer says 'of X' when creating the storage unit. This eliminates the confusing 1 of 3 -> 2 of 2 dialog heading.
- Improved compatibility with IE and Safari.
- The installer has been streamlined.
Also, I was pleasantly surprised today when I logged in and found 19 comments from my last blog entry. I'm not used to so many, so hadn't been checking. I'll be checking more here. I'll also write a blog entry to address many of the issues raised in them.
You can download the latest from sourceforge.
20101119
New FreeNAS Beta (r5606)
Just after the release of the first beta, a couple of serious problems came to life. As such, we've respun the release to fix these issues.
- gmirror error displayed bogusly
- the extremely long write times for disks
- The lack of feedback during the installation (although with the significantly faster imaging, this is much less of an issue).
- Default ownership and permission for Windows shares has been fixed
- Shares are browseable by default now
- The extra and redundant steps in the installer have been eliminated
- The inconsistent menus in the installer have been made regular
- A ZFS issue on reboot has been corrected
- Multi-line config fields have been fixed
- Problems with snmp have been resolve
- proftpd's config file is now generated properly the second time
- minor nits fixed in many places
20101118
FreeNAS 8 Beta released
iXsystems is pleased to announced FreeNAS 8.0 Beta. FreeNAS 8.0 has undergone a complete rewrite. We've redesigned the GUI to be easier to use and extend. We've upgraded many technologies in the system for improved hardware support, faster I/O, better modularity, and easier upgrades. We trust that you'll find the system easier to use and, in time, much more feature rich than the current FreeNAS offering.
The base system has migrated from FreeBSD 7.x and the m0m0wall build system to FreeBSD 8.1-RELEASE and NanoBSD. The system startup has migrated from the older php scripts to the standard FreeBSD rc.d boot system. We've pushed many of the bug fixes and system improvements back into FreeBSD.
We've rewritten the GUI using Python and Django. We've completely removed the old php system. In addition to Django, we're using Dojango and Dojo to implement AJAX features. The new system is much more modular than the old system. We will use this modularity in a future version for easy integration of custom features into your FreeNAS box.
The installer has been rewritten using pc-sysinstall, the future FreeBSD installation technology. The scripts have a similar feel to the old PHP scripts for users of the current system. The ISO now is only an installer. You can no longer run in live mode from a CDROM.
The installation types have changed; there's no longer an embedded or full install, nor can the image be installed on a data disk. You must now install FreeNAS onto a dedicated device. FreeNAS supports USB flash, CompactFlash, hard drives, ssd or any other mass storage device supported by FreeBSD.
FreeNAS 8.0 features ZFS version 14.
FreeNAS 8.0 beta has retained the core functionality of a storage appliance. The media center features of the box have not been reimplemented in the core FreeNAS package. A media center add-on package will provide this functionality in the future. We've focused on creating a robust, easy-to-use, and extensible system. We're creating the base to allow other types of packages to be added, such as printer support, scanner support, or home automation.
To help prioritize what current features are turned into packages in future FreeNAS releases, please visit http://support.freenas.org/ to provide feedback. Please add feature requests tickets. If a feature you would like to see in FreeNAS already has a ticket please just subscribe to it add a small comment, even if it's a "++." It will help us better judge and meet community needs.
You can download FreeNAS from Source Forge and read all the release notes on our wiki.
The base system has migrated from FreeBSD 7.x and the m0m0wall build system to FreeBSD 8.1-RELEASE and NanoBSD. The system startup has migrated from the older php scripts to the standard FreeBSD rc.d boot system. We've pushed many of the bug fixes and system improvements back into FreeBSD.
We've rewritten the GUI using Python and Django. We've completely removed the old php system. In addition to Django, we're using Dojango and Dojo to implement AJAX features. The new system is much more modular than the old system. We will use this modularity in a future version for easy integration of custom features into your FreeNAS box.
The installer has been rewritten using pc-sysinstall, the future FreeBSD installation technology. The scripts have a similar feel to the old PHP scripts for users of the current system. The ISO now is only an installer. You can no longer run in live mode from a CDROM.
The installation types have changed; there's no longer an embedded or full install, nor can the image be installed on a data disk. You must now install FreeNAS onto a dedicated device. FreeNAS supports USB flash, CompactFlash, hard drives, ssd or any other mass storage device supported by FreeBSD.
FreeNAS 8.0 features ZFS version 14.
FreeNAS 8.0 beta has retained the core functionality of a storage appliance. The media center features of the box have not been reimplemented in the core FreeNAS package. A media center add-on package will provide this functionality in the future. We've focused on creating a robust, easy-to-use, and extensible system. We're creating the base to allow other types of packages to be added, such as printer support, scanner support, or home automation.
To help prioritize what current features are turned into packages in future FreeNAS releases, please visit http://support.freenas.org/ to provide feedback. Please add feature requests tickets. If a feature you would like to see in FreeNAS already has a ticket please just subscribe to it add a small comment, even if it's a "++." It will help us better judge and meet community needs.
You can download FreeNAS from Source Forge and read all the release notes on our wiki.
20101028
Using devfs.conf as a porting aide
I've recently been given the task of moving some software from FreeBSD 4.x to FreeBSD 6.x on a consulting basis. This move was very simple and easy, except for one area: serial device names.
In the great tty-rewrite to make it MP safe that was done, there were a number of name changes that were unavoidable when making the tty layer more uniform between drivers. Unfortunately, sio was one of the drivers that had its names changed. This company used many multi-port expansion cards, so finding all the places where /dev/cuaaX was hard coded was difficult.
To validate the rest of the software, I created the following /etc/devfs.conf file to allow the old names to work while I hunted down all the places they were used.
These blocks were repeated for each of the serial devices in the system (I wrote a quick script to generate them for all 12 devices). One thing to remember is that the 11th device is named "/dev/cuada" not "/dev/cuad10", so you need to print the unit number as hex.
You could easily extend this to FreeBSD 7 the names changed again when FreeBSD moved from sio to uart.
again, it is a simple matter to look over the unit numbers necessary.
Note, this will only work for devices that are statically created at boot time. If you have a number of usb serial devices on a newer FreeBSD system that are replacing an older sio based FreeBSD 4.x system, you may need to use devfs.rules to accomplish this transition, which is beyond the scope of this article.
In the great tty-rewrite to make it MP safe that was done, there were a number of name changes that were unavoidable when making the tty layer more uniform between drivers. Unfortunately, sio was one of the drivers that had its names changed. This company used many multi-port expansion cards, so finding all the places where /dev/cuaaX was hard coded was difficult.
To validate the rest of the software, I created the following /etc/devfs.conf file to allow the old names to work while I hunted down all the places they were used.
# 4.x compat names on 6.x
link cuad0 cuaa0
link cuad0.init cuaia0
link cuad0.lock cuala0
link ttyd0.init ttyid0
link ttyd0.lock ttyld0
These blocks were repeated for each of the serial devices in the system (I wrote a quick script to generate them for all 12 devices). One thing to remember is that the 11th device is named "/dev/cuada" not "/dev/cuad10", so you need to print the unit number as hex.
You could easily extend this to FreeBSD 7 the names changed again when FreeBSD moved from sio to uart.
# 6.x names on 7.x system
link cuau0 cuad0
link cuau0.init cuad0.init
link cuau0.lock cuad0.lock
link ttyu0 ttyd0
link ttyu0.init ttyd0.init
link ttyu0.lock ttyd0.lock
again, it is a simple matter to look over the unit numbers necessary.
Note, this will only work for devices that are statically created at boot time. If you have a number of usb serial devices on a newer FreeBSD system that are replacing an older sio based FreeBSD 4.x system, you may need to use devfs.rules to accomplish this transition, which is beyond the scope of this article.
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