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--></style></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='color:#4472C4'>Jean-Paul,<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I think we discussed this on IRC. Reading through your summary, it still seems like it makes sense to me.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='color:#4472C4'>Great!! I am working on something else right now but will get to this soon.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#4472C4'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#4472C4'>PS. I am having an issue with the magic-folder feature that I will post to this mail alias later this week.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#4472C4'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#4472C4'>Thanks again,<o:p></o:p></span></p><p class=MsoNormal><span style='color:#4472C4'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#4472C4'> Bruce T<o:p></o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:12.0pt;color:black'>From: </span></b><span style='font-size:12.0pt;color:black'>Jean-Paul Calderone <jean-paul+tahoe-dev@leastauthority.com><br><b>Date: </b>Tuesday, September 24, 2019 at 10:23 AM<br><b>To: </b>Bruce Thompson <brucet.cisco@gmail.com><br><b>Cc: </b><tahoe-dev@tahoe-lafs.org>, Pierre Malhaire <pierre.malhaire@gmail.com>, eduardo gonzalez <eduardogonzalez@ged-innovations.com>, Brian Thompson <brianbthompson@sbcglobal.net><br><b>Subject: </b>Re: Feature request and proposal for Tahoe-LAFS<o:p></o:p></span></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal>On Mon, Sep 16, 2019 at 2:31 PM brucet <<a href="mailto:brucet.cisco@gmail.com">brucet.cisco@gmail.com</a>> wrote:<o:p></o:p></p></div><div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>I want to use Tahoe-LAFS as the storage component of a network backup application. In this application, each node hosts a backup application as well as a full Tahoe node (storage server + client). The backup application can be used to back up data on the node to the Tahoe storage network. I have found a limitation of Tahoe-LAFS that makes it less than ideal for this type of application.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Here’s the issue:<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>When you use Tahoe-LAFS with the introducer, every node is advertised as a potential storage node. This includes the local node which is also is hosting a Tahoe storage node. When the backup application is used to store local data to the Tahoe-LAFS network, it may end up putting a slice of the data on its own node. There are 2 problems with this:<o:p></o:p></p><ol start=1 type=1><li class=gmail-m3831569143768487264msolistparagraph style='mso-list:l1 level1 lfo1'>It is wasteful of storage space<o:p></o:p></li></ol><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:1.0in'>The local node already has a copy of the data so storing a slice locally does not really improve resiliency.<o:p></o:p></p><ol start=2 type=1><li class=gmail-m3831569143768487264msolistparagraph style='mso-list:l0 level1 lfo2'>It reduces resiliency<o:p></o:p></li></ol><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:1.0in'>If the hard drive fails on the node, Tahoe slice stored on it may be lost.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:1.0in'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>I have discussed this issue with people on the tahoe-lafs IRC node and we came up with a proposal for a new feature which addresses this issue.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>The proposed new feature is to create a new configuration flag for the Tahoe-LAFS client which prevents the client from storing data to its local storage node (“don’t_use_local_storage”). When the flag is set, the client gets the name of the local storage node from tahoe.cfg using the nickname attribute of the [node] section. When the client creates a list of storage nodes to store content to, it excludes this particular node from the list.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Make sense?<o:p></o:p></p></div></div></blockquote><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Heya Bruce,<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I think we discussed this on IRC. Reading through your summary, it still seems like it makes sense to me.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Jean-Paul<o:p></o:p></p></div><div><p class=MsoNormal> <o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> Bruce T<o:p></o:p></p></div></div><p class=MsoNormal>_______________________________________________<br>tahoe-dev mailing list<br><a href="mailto:tahoe-dev@tahoe-lafs.org" target="_blank">tahoe-dev@tahoe-lafs.org</a><br><a href="https://tahoe-lafs.org/cgi-bin/mailman/listinfo/tahoe-dev" target="_blank">https://tahoe-lafs.org/cgi-bin/mailman/listinfo/tahoe-dev</a><o:p></o:p></p></blockquote></div></div></div></body></html>