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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Level: X-Spam-Flag: NO X-Rspamd-Queue-Id: 3865621206 X-Rspamd-Action: no action X-Rspamd-Server: rspamd1.dmz-prg2.suse.org X-Spamd-Result: default: False [-4.51 / 50.00]; BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; FUZZY_RATELIMITED(0.00)[rspamd.com]; RCVD_VIA_SMTP_AUTH(0.00)[]; ARC_NA(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; MIME_TRACE(0.00)[0:+]; RCPT_COUNT_TWO(0.00)[2]; RCVD_TLS_ALL(0.00)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:dkim,suse.de:mid,suse.de:email]; DKIM_TRACE(0.00)[suse.de:+] X-Spam-Score: -4.51 On 9/3/25 13:55, Stefanie Leisestreichler (Febas) wrote: > Hi. > I have the system layout shown below. > > To avoid data loss, I want to change HDs which have about 46508 hours of > up time. > > I thought, instead of degrading, formatting, rebuilding and so on, I could > - shutdown the computer > - take i.e. /dev/sda and do > - dd bs=98304 conv=sync,noerror if=/dev/sda of=/dev/sdX (X standig for > device name of new disk) > Why would you do that? In the end, you will have to transfer data from the entire disk (to a new disk). And that will be the main drag, at it'll take ages. And there it doesn't matter if you use 'dd' or md resync; both will be taking roughly the same time. > Is it save to do it this way, presuming the array is in AA-State? > I would not recommend it. Replacing drives is _precisely_ why RAID was created in the first place, so really there is no difference between replacing a faulty drive or replacing a non-faulty drive. So I would strongly recommend to use MD tools to replace the drive; it will serve as a nice exercise on what to do in case of a real fault :-) Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich