Get more RAM File System Space (HPUX Recovery Document)

[FTSE SysAdmin]

Hi,

The procedure to increase the RAM file-system space on "Chapter 4 - System Recovery" PDF is wrong or at least does not work.

I quote:

loadfile mkfs tar chroot
mknod /dev/ram b 9 0x180000
mknod /dev/rram c 9 0x180000
mkfs /dev/rram

the make FS cannot open the device /dev/rram

the devices are:
brw-r--r-- 0x18000 /dev/ram
crw-r--r-- 0x18000 /dev/rram

Even chaning them to 666 didn't help.

Does someone know a possible work-around to solve this issue?

[Pete Randall]

I did a search on "ramdisk" and found this thread (and several others) - maybe it will help:

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=227456


Pete

[Steven E. Protter]

I have never seen the document. I'd like to read it to further assist you. Can you post a copy of it or a link to it?

SEP

[RAC_1]

My notes are as follows.

2) # set up the device files and mount the ramdisk:

2) # create the device files with major 9 (both b and c),

2) # and minor 0xVSSSSS, where "V" is the volume num,

2) # and "SSSSS" is the number of sectors in the ram

2) # disk, each sector is 256 bytes.

2) mknod /dev/rram1 c 9 0x101000

2) mknod /dev/ram1 b 9 0x101000 # that's 1MB

2) mkfs -F hfs /dev/rram1 # no point in VxFS here

2) mount /dev/ram1 /ramdisk

As everybody (especially Bill :-) pointed out:

THIS IS UNSUPPORTED, dangerous, and such...

[FTSE SysAdmin]

Thanks,

but unfortunately didn't help :(

This system is HP-UX and I'm at present moment with a reduced kernel (boot from CDROM) trying to fix it... but I need to be able to increase the ramdisk to load the commands to repair the LVM and mount the root-FS.

HP documentation about this (how to increase the ram disk) is wrong or does not work :(

So I'm "stucked" with a system unable to boot from the primary disks :(

[Robert-Jan Goossens]

Hi,

Check this doc and the warning!

Document description: The use of virtual ramdisc (as a file in memory) on HP-UX
Document id: KBAN00000674

*** DO NOT USE RAMDISC - IT IS NEITHER BENEFICIAL, DOCUMENTED, NOR SUPPORTED ***

US
http://www2.itrc.hp.com/service/cki/docDisplay.do?docLocale=en_US&docId=200000062684407

Europe
http://www4.itrc.hp.com/service/cki/docDisplay.do?docLocale=en_US&docId=200000062684407

Regards,
Robert-Jan

[FTSE SysAdmin]

The document that I quote as wrong can be found on the following link:

http://www4.itrc.hp.com/service/iv/docDisplay.do?docId=prodITRC/DE_SW_UX_swrec_EN_01_E/SystemRecovery.pdf

The mkfs couldn't read the /dev/rram to create the FS however both devices were there and accessible

[RAC_1]

Doesn't mkfs require an argument??

mkfs -F hfs /dev/ram

[FTSE SysAdmin]

Doesn't mkfs require an argument??

mkfs -F hfs /dev/ram

----------------------------------

It assumed hfs by default... however returned as cannot open the device.

Here is the example (following the procedure)

# loadfile mkfs tar chroot
# pwd
/
# mknod /dev/ram b 9 0x180000
# mknod /dev/rram c 9 0x180000
# mkfs /dev/rram
mkfs (hfs): Cannot open /dev/rram
mkfs (hfs): No such device or address
# ll /dev/ram /dev/rram
brw-r--r-- 1 root sys 9 0x180000 May 5 15:07 /dev/ram
crw-r--r-- 1 root sys 9 0x180000 May 5 15:07 /dev/rram


even with mkfs -F hfs

[RAC_1]

lssf /dev/rram

Does it give something?? Is driver "ram" in kernel??