From mboxrd@z Thu Jan 1 00:00:00 1970 From: Neil Brown Subject: Re: RAID6 grow unexpected results Date: Fri, 23 Oct 2015 09:37:05 +1100 Message-ID: <87io5yzg1a.fsf@notabene.neil.brown.name> References: Mime-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha256; protocol="application/pgp-signature" Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Liwei , linux-raid@vger.kernel.org List-Id: linux-raid.ids --=-=-= Content-Type: text/plain Liwei writes: > Hi list, > I tried growing a RAID6 array by executing the mdadm --add and > mdadm --grow --raid-devices commands. Usually that should run fine and > I can continue with pvresize. That is incorrect. You cannot run "pvresize" until the reshape completes. > > This time however, the actual usable raid array size did not > change even though reshape begins. In my confusion, I decided to > reboot. That didn't solve the problem (and apparently the reshape was > interrupted, but mdadm shows the grown array as clean?) Clean is expected. It will be in an intermediate state, part has reshaped to extra devices, part is still the original. > > I then executed mdadm --grow --size=max, which seemed to have > increased the array size, but apparently by too much. Now I'm getting > "attempt to access beyond end of device" errors for each of the > component drives. A new reshape operation has also begun, which I > expect would fail as the array size is now too big. "--size" isn't the same as "--array-size". "--size" is the size of the component devices to use. The "attempt to access beyond end of device" errors are unexpected but presumably related o the "--size=max". Maybe the 'max' chosen was too large. That suggests a bug somewhere. You probably want to reduce that size back to where it was. > > What did I do wrong and how can I remedy this? Could we start with "mdadm --examine" status of all devices, "mdadm --detail" of the array, and all kernel messages that could possibly relate to the array since you first started this exercise? NeilBrown > > Liwei > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBCAAGBQJWKWUSAAoJEDnsnt1WYoG5ncIQALdIgdPSf3qsyLbPQ7dk0QY3 hDDZFyIJLdizNKVDV2L64nU8WdCeO5WPsZhIpz9liheFdm2eDkFwtROyqXcXgqpS W9Ts7mvnExBJfdtxwIwZ/MWCXUbxuRPCjYJR9p8FuCqQuhtymLs+0WdVKkuGiwK0 Vo/jXAx76kpPu3awlR8YnL+6KGpOxzb9k8YY5wPAspcHxjqxOobpgjEU3BmESBvA eA0qMJrO+oFGk9XwFqW20n2x+4b4WsAe4WGvXcE5tSH542iAbBwJ2h9k/Z1KDJM/ UcJiUtjk7Vgx30FsLL/xjJyMgSEAd4oZ/UxO+n09A9Hcarzz6E6IHDrsMKpakH7W t7S9h/ND7F3l0jKSsUW9z2ISbA+eSs0EteioNskCbRu7XvJA5b7gAkrJ0XA2nN0g eaHl/MWXuihcdFGOvoA+9B8XgjdDcum+2agsBS7e/F1EHPJkmfYP/AJpowZS+GMX bpsaMEKneS5vZOAm+YdI7Nc2kRO3mYDnnf2o9+ubqzjciA9pG3BoDvnLgvfujXkR FDDNGz8HSP4bT3bw/AwJg88crx0mJr6N0Y8gx/ev3d2mWP2j5mnL0ki5SqWRNaR1 JQZ1strvhrg4otVBo84jCS/wsFA+PFhxZ/P+P+o15xogyk0xGoBuB1+Z8coxmKKa tZj2meK90bm06E1SRPQO =Yhqy -----END PGP SIGNATURE----- --=-=-=--