From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id 06FD26CC14 for ; Wed, 31 Mar 2021 09:04:57 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id E2742B547 for ; Wed, 31 Mar 2021 09:04:26 +0200 (CEST) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [212.186.127.180]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS id E85E0B539 for ; Wed, 31 Mar 2021 09:04:25 +0200 (CEST) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id B8FAB42944 for ; Wed, 31 Mar 2021 09:04:25 +0200 (CEST) To: Proxmox VE development discussion , Stoiko Ivanov References: <20210330182604.15292-1-s.ivanov@proxmox.com> From: Aaron Lauterer Message-ID: <29540fcc-d544-f8cb-f532-58ca12ed6b3f@proxmox.com> Date: Wed, 31 Mar 2021 09:04:24 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.9.0 MIME-Version: 1.0 In-Reply-To: <20210330182604.15292-1-s.ivanov@proxmox.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-SPAM-LEVEL: Spam detection results: 0 AWL -0.018 Adjusted score from AWL reputation of From: address KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment NICE_REPLY_A -0.001 Looks like a legit reply (A) RCVD_IN_DNSWL_MED -2.3 Sender listed at https://www.dnswl.org/, medium trust SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Subject: Re: [pve-devel] [PATCH docs] zfs: add section on zpool-features X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 31 Mar 2021 07:04:57 -0000 Looks good to me. Reviewed-By: Aaron Lauterer On 3/30/21 8:26 PM, Stoiko Ivanov wrote: > primarily in order to warn users booting from ZFS with grub. > > Signed-off-by: Stoiko Ivanov > --- > local-zfs.adoc | 36 ++++++++++++++++++++++++++++++++++++ > 1 file changed, 36 insertions(+) > > diff --git a/local-zfs.adoc b/local-zfs.adoc > index 4819678..a003a7c 100644 > --- a/local-zfs.adoc > +++ b/local-zfs.adoc > @@ -699,3 +699,39 @@ in the pool will opt in for small file blocks). > ---- > # zfs set special_small_blocks=0 / > ---- > + > +[[sysadmin_zfs_features]] > +ZFS Pool Features > +~~~~~~~~~~~~~~~~~ > + > +Changes to the on-disk format in ZFS are only done between major version changes > +and are specified through *features*. All features and the general mechanism > +are well documented in the `zpool-features(5)` manpage. > + > +Since enabling new features can render a pool not importable by an older version > +of ZFS, this needs to be actively done by the administrator by running > +`zpool upgrade` on the pool (see the `zpool-upgrade(8)` manpage). > + > +Unless you need to use one of the new features there is no upside to enabling > +the new features. > + > +On the other hand there are a few downsides on enabling new features: > + > +* A system, with root on ZFS, still booting with `grub` will become unbootable > + if a new feature is active on the rpool, due to the incompatible > + implementation of ZFS in grub. > +* The system will not be able to boot with an older kernel, which is still > + shipping the old ZFS modules > +* Booting an older {pve} ISO to do repair a non-booting system likewise will not > + work > + > +IMPORTANT: Do not upgrade your rpool if your system is still booted with `grub`. > +Systems installed before PVE 5.4, and systems booting with legacy boot (see > +xref:sysboot_determine_bootloader_used[how to determine the bootloader]), as > +this will render your system unbootable. > + > +.Enable new features for a pool: > +---- > +# zpool upgrade > +---- > + >