<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class="">Zane</div><div class=""><br class=""></div><blockquote type="cite" class="">On Feb 20, 2018, at 9:00 AM, <a href="mailto:simh-request@trailing-edge.com" class="">simh-request@trailing-edge.com</a> wrote:<br class=""></blockquote><div><blockquote type="cite" class=""><br class="Apple-interchange-newline"><div class=""><span class="" style="font-family: Monaco; font-size: 12px; float: none; display: inline !important;">Date: Mon, 19 Feb 2018 21:55:00 -0800</span><br class="" style="font-family: Monaco; font-size: 12px;"><span class="" style="font-family: Monaco; font-size: 12px; float: none; display: inline !important;">From: Zane Healy <</span><a href="mailto:healyzh@avanthar.com" class="" style="font-family: Monaco; font-size: 12px;">healyzh@avanthar.com</a><span class="" style="font-family: Monaco; font-size: 12px; float: none; display: inline !important;">></span><br class="" style="font-family: Monaco; font-size: 12px;"><span class="" style="font-family: Monaco; font-size: 12px; float: none; display: inline !important;">To: Zane Healy <</span><a href="mailto:healyzh@avanthar.com" class="" style="font-family: Monaco; font-size: 12px;">healyzh@avanthar.com</a><span class="" style="font-family: Monaco; font-size: 12px; float: none; display: inline !important;">></span><br class="" style="font-family: Monaco; font-size: 12px;"><span class="" style="font-family: Monaco; font-size: 12px; float: none; display: inline !important;">Cc: simh <</span><a href="mailto:simh@trailing-edge.com" class="" style="font-family: Monaco; font-size: 12px;">simh@trailing-edge.com</a><span class="" style="font-family: Monaco; font-size: 12px; float: none; display: inline !important;">></span><br class="" style="font-family: Monaco; font-size: 12px;"><span class="" style="font-family: Monaco; font-size: 12px; float: none; display: inline !important;">Subject: Re: [Simh] VAX Tape Emulation?</span><br class="" style="font-family: Monaco; font-size: 12px;"><span class="" style="font-family: Monaco; font-size: 12px; float: none; display: inline !important;">Message-ID: <</span><a href="mailto:1665A095-D246-4272-91AC-EF2BBC45A1F7@avanthar.com" class="" style="font-family: Monaco; font-size: 12px;">1665A095-D246-4272-91AC-EF2BBC45A1F7@avanthar.com</a><span class="" style="font-family: Monaco; font-size: 12px; float: none; display: inline !important;">></span><br class="" style="font-family: Monaco; font-size: 12px;"><span class="" style="font-family: Monaco; font-size: 12px; float: none; display: inline !important;">Content-Type: text/plain; charset=utf-8</span></div></blockquote><blockquote type="cite" class=""><br class="Apple-interchange-newline"><div class=""><span style="font-family: Monaco; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">I’m backing MONK up over the Cluster to a “tape drive” on RENNY.</span><br style="font-family: Monaco; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""></div></blockquote></div><div class=""><br class=""></div>I'm really puzzled why you prefer to backup to a SIMH virtual tape image. You can create empty SIMH VAX virtual disk drives for your clustered virtual VAX and backup directly to a save set on disk. You can even make a backup disk image—bootable on a SIMH Alpha, when that arrives. You can read files individually on a backup disk image any time you want to. There is no need to go through the entire save set to find one file.<div class=""><br class=""></div><div class="">As far as your backup speed, you might be rate limited by the XOR blocks being added and by the (less likely) SIMH virtual tape formatting. You should be able to test that by doing a backup on the SIMH VAX to the virtual tape drive to take the network out of the picture. You can control how often XOR blocks are written, or eliminate them altogether.<div class=""><br class=""><div class=""><div style="font-family: 'Helvetica Neue'; orphans: 2; widows: 2; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Larry Baker<br class="">US Geological Survey<br class="">650-329-5608<br class=""><a href="mailto:baker@usgs.gov" class="">baker@usgs.gov</a><br class=""><br class=""></div></div></div></div></body></html>