Did you run "touch" from a client ? ZFS and UFS are different in general but in response to a local "touch" command neither need to generate immediate I/O and in response to a client "touch" both do.
-r Ayaz Anjum writes: > HI ! > > Well as per my actual post, i created a zfs file as part of Sun cluster > HAStoragePlus, and then disconned the FC cable, since there was no active > IO hence the failure of disk was not detected, then i touched a file in > the zfs filesystem, and it went fine, only after that when i did sync then > the node panicked and zfs filesystem is failed over to other node. On the > othernode the file i touched is not there in the same zfs file system > hence i am saying that data is lost. I am planning to deploy zfs in a > production NFS environment with above 2TB of Data where users are > constantly updating file. Hence my concerns about data integrity. Please > explain. > > thaks > > Ayaz Anjum > > > > > Darren Dunham <[EMAIL PROTECTED]> > Sent by: [EMAIL PROTECTED] > 03/12/2007 05:45 AM > > To > zfs-discuss@opensolaris.org > cc > > Subject > Re: Re[2]: [zfs-discuss] writes lost with zfs ! > > > > > > > > I have some concerns here, from my experience in the past, touching a > > file ( doing some IO ) will cause the ufs filesystem to failover, unlike > > > zfs where it did not ! Why the behaviour of zfs different than ufs ? > > UFS always does synchronous metadata updates. So a 'touch' that creates > a file is going to require a metadata write. > > ZFS writes may not necessarily hit the disk until a transaction group > flush. > > > is not this compromising data integrity ? > > It should not. Is there a scenario that you are worried about? > > -- > Darren Dunham [EMAIL PROTECTED] > Senior Technical Consultant TAOS http://www.taos.com/ > Got some Dr Pepper? San Francisco, CA bay area > < This line left intentionally blank to confuse you. > > _______________________________________________ > zfs-discuss mailing list > zfs-discuss@opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss > > > > > > > > > > -------------------------------------------------------------------------------------------------- > > > Confidentiality Notice : This e-mail and any attachments are > confidential to the addressee and may also be privileged. If you are > not the addressee of this e-mail, you may not copy, forward, disclose or > otherwise use it in any way whatsoever. If you have received this e-mail > by mistake, please e-mail the sender by replying to this message, and > delete the original and any print out thereof. > > <br><font size=3 face="sans-serif">HI !</font> > <br> > <br><font size=3 face="sans-serif">Well as per my actual post, i created > a zfs file as part of Sun cluster HAStoragePlus, and then disconned the > FC cable, since there was no active IO hence the failure of disk was not > detected, then i touched a file in the zfs filesystem, and it went fine, > only after that when i did sync then the node panicked and zfs filesystem > is failed over to other node. On the othernode the file i touched is not > there in the same zfs file system hence i am saying that data is lost. > I am planning to deploy zfs in a production NFS environment with above > 2TB of Data where users are constantly updating file. Hence my concerns > about data integrity. Please explain.</font> > <br> > <br><font size=3 face="sans-serif">thaks</font> > <br> > <br><font size=3 face="sans-serif">Ayaz Anjum<br> > </font> > <br> > <br> > <br> > <table width=100%> > <tr valign=top> > <td width=40%><font size=1 face="sans-serif"><b>Darren Dunham <[EMAIL > PROTECTED]></b> > </font> > <br><font size=1 face="sans-serif">Sent by: [EMAIL PROTECTED]</font> > <p><font size=1 face="sans-serif">03/12/2007 05:45 AM</font> > <td width=59%> > <table width=100%> > <tr> > <td> > <div align=right><font size=1 face="sans-serif">To</font></div> > <td valign=top><font size=1 > face="sans-serif">zfs-discuss@opensolaris.org</font> > <tr> > <td> > <div align=right><font size=1 face="sans-serif">cc</font></div> > <td valign=top> > <tr> > <td> > <div align=right><font size=1 face="sans-serif">Subject</font></div> > <td valign=top><font size=1 face="sans-serif">Re: Re[2]: [zfs-discuss] > writes lost with zfs !</font></table> > <br> > <table> > <tr valign=top> > <td> > <td></table> > <br></table> > <br> > <br> > <br><font size=2><tt>> I have some concerns here, from my experience > in the past, touching a <br> > > file ( doing some IO ) will cause the ufs filesystem to failover, > unlike <br> > > zfs where it did not ! Why the behaviour of zfs different than ufs > ?<br> > <br> > UFS always does synchronous metadata updates. So a 'touch' that > creates<br> > a file is going to require a metadata write.<br> > <br> > ZFS writes may not necessarily hit the disk until a transaction group<br> > flush. <br> > <br> > > is not this compromising data integrity ?<br> > <br> > It should not. Is there a scenario that you are worried about?<br> > <br> > -- <br> > Darren Dunham > > [EMAIL PROTECTED]<br> > Senior Technical Consultant TAOS > http://www.taos.com/<br> > Got some Dr Pepper? > San Francisco, CA bay area<br> > < This line left intentionally blank to > confuse you. ><br> > _______________________________________________<br> > zfs-discuss mailing list<br> > zfs-discuss@opensolaris.org<br> > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss<br> > </tt></font> > <br><font size=2 face="sans-serif"><br> > <br> > <br> > <br> > <br> > <br> > <br> > <br> > -------------------------------------------------------------------------------------------------- > <br> > Confidentiality Notice : This e-mail and any attachments > are > confidential to the addressee and may also be privileged. > If > you are not the addressee of this e-mail, you may > not copy, forward, disclose or otherwise use it in any way whatsoever. > If you have received this e-mail by mistake, please e-mail > the sender by replying to this message, and delete the original and > any print out thereof. </font> > _______________________________________________ > zfs-discuss mailing list > zfs-discuss@opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
