Aqui está o log do k3b salvo:
Devices
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PIONEER DVD-RW DVR-K16RA 1.16 (/dev/sr0, CD-R, CD-RW, CD-ROM, DVD-ROM, DVD-R, DVD-RW, DVD-R DL, DVD+R, DVD+RW, DVD+R DL) [DVD-ROM, DVD-R Sequential, DVD-R Dual Layer Sequential, DVD-R Dual Layer Jump, DVD-RW Restricted Overwrite, DVD-RW Sequential, DVD+RW, DVD+R, DVD+R Dual Layer, CD-ROM, CD-R, CD-RW] [SAO, TAO, RAW, SAO/R96P, SAO/R96R, RAW/R16, RAW/R96P, RAW/R96R, Restricted Overwrite, Layer Jump] [%7]
System
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K3b Version: 2.0.2
KDE Version: 4.9.5
QT Version: 4.8.3
Kernel: 3.7.0-7-generic
Used versions
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cdrecord: 3.0
cdrecord
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scsidev: '/dev/sr0'
devname: '/dev/sr0'
scsibus: -2 target: -2 lun: -2
Warning: Open by 'devname' is unintentional and not supported.
Linux sg driver version: 3.5.27
SCSI buffer size: 64512
/usr/bin/cdrecord: Warning: Cannot read drive buffer.
/usr/bin/cdrecord: Warning: The DMA speed test has been skipped.
Cdrecord-ProDVD-ProBD-Clone 3.00 (i686-pc-linux-gnu) Copyright (C) 1995-2010 J�rg Schilling
TOC Type: 1 = CD-ROM
Using libscg version 'schily-0.9'.
Driveropts: 'burnfree'
atapi: 1
Device type : Removable CD-ROM
Version : 5
Response Format: 2
Capabilities :
Vendor_info : 'PIONEER '
Identifikation : 'DVD-RW DVR-K16RA'
Revision : '1.16'
Device seems to be: Generic mmc2 DVD-R/DVD-RW/DVD-RAM.
Current: CD-R
Profile: DVD+R/DL
Profile: DVD+R
Profile: DVD+RW
Profile: DVD-R/DL layer jump recording
Profile: DVD-R/DL sequential recording
Profile: DVD-RW sequential recording
Profile: DVD-RW restricted overwrite
Profile: DVD-R sequential recording
Profile: DVD-ROM
Profile: CD-RW
Profile: CD-R (current)
Profile: CD-ROM
Using generic SCSI-3/mmc CD-R/CD-RW driver (mmc_cdr).
Driver flags : MMC-3 SWABAUDIO BURNFREE
Supported modes: TAO PACKET SAO SAO/R96P SAO/R96R RAW/R16 RAW/R96P RAW/R96R LAYER_JUMP
Drive buf size : 1267712 = 1238 KB
FIFO size : 4194304 = 4096 KB
Track 01: data 693 MB
Total size: 796 MB (78:52.88) = 354966 sectors
Lout start: 796 MB (78:54/66) = 354966 sectors
Current Secsize: 2048
ATIP info from disk:
Indicated writing power: 4
Disk Is not unrestricted
Disk Is not erasable
Disk sub type: Medium Type A, low Beta category (A-) (2)
ATIP start of lead in: -12508 (97:15/17)
ATIP start of lead out: 359845 (79:59/70)
Disk type: Short strategy type (Phthalocyanine or similar)
Manuf. index: 22
Manufacturer: Ritek Co.
Capacity Blklen/Sparesz. Format-type Type
0 2048 0x00 Unformated or Blank Media
Blocks total: 359845 Blocks current: 359845 Blocks remaining: 4879
Starting to write CD/DVD/BD at speed 24 in real force SAO mode for single session.
Last chance to quit, starting real write in 3 seconds.
2 seconds.
1 seconds.
0 seconds. Operation starts.
Waiting for reader process to fill input buffer ... input buffer ready.
BURN-Free is OFF.
Turning BURN-Free on
Performing OPC...
Sending CUE sheet...
Writing pregap for track 1 at -150
Starting new track at sector: 0
Track 01: 0 of 693 MB written.
Track 01: 1 of 693 MB written (fifo 98%) 0.4x.
Track 01: 2 of 693 MB written (fifo 100%) [buf 96%] 10.1x.
Track 01: 3 of 693 MB written (fifo 98%) [buf 96%] 10.7x.
Track 01: 4 of 693 MB written (fifo 96%) [buf 27%] 2.4x.
/usr/bin/cdrecord: Input/output error. write_g1: scsi sendcmd: no error
CDB: 2A 00 00 00 09 B0 00 00 1F 00
status: 0x2 (CHECK CONDITION)
Sense Bytes: 71 00 03 00 00 27 34 0E 00 00 00 00 0C 00 00 00
Sense Key: 0x3 Medium Error, deferred error, Segment 0
Sense Code: 0x0C Qual 0x00 (write error) Fru 0x0
Sense flags: Blk 10036 (not valid)
cmd finished after 0.001s timeout 200s
/usr/bin/cdrecord: A write error occured.
/usr/bin/cdrecord: Please properly read the error message above.
write track data: error after 5079040 bytes
Writing time: 56.095s
Average write speed 167.0x.
Min drive buffer fill was 27%
Fixating...
Fixating time: 0.012s
/usr/bin/cdrecord: fifo had 144 puts and 81 gets.
/usr/bin/cdrecord: fifo was 0 times empty and 40 times full, min fill was 82%.
cdrecord command:
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/usr/bin/cdrecord -v gracetime=2 dev=/dev/sr0 speed=24 -sao driveropts=burnfree -force -data -tsize=354966s -
Parece que você está tentando gravá-lo em um CD padrão, um CD é pequeno demais para conter o Ubuntu agora, você precisa usar um DVD ou uma unidade flash de 1GB + ( unetbootin funciona bem para drives flash)
O unetbootin está disponível no centro de software