Date: Mon, 24 Feb 2014 12:26:04 -0700 (MST) From: Warren Block <wblock@wonkity.com> To: Chris Stankevitz <chrisstankevitz@gmail.com> Cc: freebsd-questions@freebsd.org Subject: Re: gptids are not symlinks to /dev/da* Message-ID: <alpine.BSF.2.00.1402241208090.2118@wonkity.com> In-Reply-To: <CAPi0pstLDDzLvuzzcPuN1LbgrAjiTu=vRAyxxphgcimuScMoNA@mail.gmail.com> References: <CAPi0pstLDDzLvuzzcPuN1LbgrAjiTu=vRAyxxphgcimuScMoNA@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Mon, 24 Feb 2014, Chris Stankevitz wrote: > Hello, > > Can you help fill in some detail for the questions I list below? Thank you! > > > Facts: > > 1. zpool status shows "gptids" like so: > gptid/affd7a1f-9c50-11e3-a81e-002590caf078 > > 2. gptids are located under /dev/gptid/ and /dev > > 3. smartctl does not like gptids but does like /dev/da* "smartctl -a > /dev/gptid/affd7a1f-9c50-11e3-a81e-002590caf078" > > 4. "man gptid" comes up blank > > 5. the freebsd handbook does not describe gptid > > 6. google "freebsd gptid" returns a bunch of random stuff > > > Questions: > > Q1: What is a gptid? > > A1: It's some kind of system by which drives have the same device name > across reboots Not device name, but a label. Although the correct one should work in place of a device name. I use GPT partition labels, but have never bothered with the GUIDs. > Q2: How does FreeBSD know which drive corresponds to which gptid? > When is the gptid assigned? > > A2: gptids are written to the first block of the disk during manufacture. Generated when the structure is created, I think. > Q3: Can I use it like a regular /dev/da? device? > > A3: No. For example, smartctl takes /dev/da* but not /dev/gptid/* smartctl wants a device, but GPTIDs refer to partitions. There is a GUID for the whole disk, but it appears to not be shown. > Q5: Why am I unable to figure out what is a gptid even after > attempting to read documentation/google? GPT IDs and labels are created by the geom_label class, described in glabel(8).
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?alpine.BSF.2.00.1402241208090.2118>