-
Starnge dd behaviour in 8.2.0
Dear All -
If I use the command fdisk -l I get the usual and expected output of the style
Device Boot Start End Sectors Size Id Type
/dev/sda1 * 2048 131604479 131602432 62.8G 7 HPFS/NTFS/exFAT
/dev/sda2 131604480 1180327679 1048723200 500.1G 7 HPFS/NTFS/exFAT
/dev/sda3 1180327680 2229050879 1048723200 500.1G 7 HPFS/NTFS/exFAT
My question concerns the line
/dev/sda1 * 2048 131604479 131602432 62.8G 7 HPFS/NTFS/exFAT
Surely that means that /dev/sda1 starts at sector number 2048 and that there are 2,048 sectors at the start of /dev/sda (yes, numbered 0000-2047) allocated otherwise?
For various reasons I want to zero these initial sectors of /dev/sda using the command
dd if=/dev/zero of=/dev/sda count=2048
but to my annoyance (and very considerable damage to the system) this also zeroes the first sector of /dev/sda1.
That is, the dd command zeroes not just those sectors numbered 0000-2047 but also the sector numbered 2048: so 2049 altogether. not 2048.
I am absolutely convinced that my understanding of counts / numbers / numbering as described above was correct under 7.4.2 and that I issued commands, many times, in the manner describe without damaging /dev/sda1; (but I am a bit nervous now about checking that)!
Can anybody conform that I am right? That I am wrong? That dd under 8.2.0 is glitchy?
Thank you!
Fergus
PS And by the way (completely different and unconnected) I find the file /boot/isolinux/ifcpu64.c32 is broken in the 8.2.0 installation and I have to over-write it with the same file from 7.4.2 for things to work properly. Anybody else?
Fergus
Posting Permissions
- You may not post new threads
- You may not post replies
- You may not post attachments
- You may not edit your posts
-
Forum Rules
Dell PowerEdge R720 Server - 2x8c CPU,256Gb RAM, 128Gb SSD/3x900Gb SAS, Proxmox
$340.00
Dell PowerEdge R620 Server 2x E5-2660 v1 2.2GHz 16 Cores 256GB RAM 2x 300GB HDD
$79.19
Dell PowerEdge R730XD 28 Core Server 2X Xeon E5-2680 V4 H730 128GB RAM No HDD
$389.99
Dell PowerEdge R720XD Xeon E5-2680 V2 2.8GHz 20 Cores 256GB RAM 12x4TB
$510.00
DELL POWEREDGE T430 SERVER W/ DUAL XEON E5-2609 CPU & 16GB MEMORY
$329.00
Dell PowerEdge R620 4-Bay Server 2x Xeon E5-2690 8 Core 2.9GHz 32GB No HDD H710P
$95.63
CTO Dell PowerEdge R630 Server, 2x Xeon E5-2620V4, 64GB- 512GB RAM, 480GB SSDs
$246.67
Dell PowerEdge R620 Server 2x E5-2650 V2 = 16 Cores H710P 128GB RAM 2x 600GB SAS
$274.99
DELL EMC POWEREDGE SERVER R740xd 24 BAY NVME CHASSIS WITH PARTS 6D1DT R27KK
$199.00
CTO Dell PowerEdge R630 Server, 2x Xeon E5-2680V4, 64GB- 512GB RAM, New SSDs
$348.00