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<p>Greetings everyone,</p>
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<p style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">
<span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 12pt;">We've recently started considering Slony for purpose of migrating PostgreSQL
from old physical server to a new virtualized and </span><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 12pt;">"updated" platform.
So far, all our tests worked quite well. However, I</span>'m having trouble finding any documentation to prove or disprove that the following scenario is supported and/or will work properly (initial testing was positive though).</p>
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<p><span style="font-size: 12pt;">We would like to setup streaming replication between future Slony subscriber and our DR site beforehand, ie. <span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">before
we introduce Slony</span>. This would save us time and additional work post migration. </span></p>
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<p>It would look something like this:</p>
<p><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><span style="background-color: rgb(255, 255, 0);">"New
B" (disaster recovery site) </span><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px; background-color: rgb(255, 255, 0);"> <</span><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px; background-color: rgb(255, 255, 0);">----
Streaming replication ---- </span></span><span style="background-color: rgb(255, 255, 0);">"New A</span>"
<span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px; background-color: rgb(190, 190, 190);">
<--------Slony replication -----</span><span style="background-color: rgb(190, 190, 190);"> </span></span><span style="background-color: rgb(190, 190, 190);">"Old A" ------ existing SR ------> </span><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px; background-color: rgb(190, 190, 190);">"Old
B" (</span><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px; background-color: rgb(190, 190, 190);">DR site</span><span style="font-family: Calibri, Arial, Helvetica, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px; background-color: rgb(190, 190, 190);">)</span></p>
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<ul>
<li>Streaming replication between "New A" and "New B" <u>would be setup first</u></li><li>Then we would setup Slony replication between "Old A" and "New A"</li><li><span style="font-size: 12pt;">Slony replication Set would be moved from "Old A" to "New A"</span></li><li><span style="font-size: 12pt;">Slon process would be stopped and Slony Schema would be removed </span><br>
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<div>Has anyone done something similar? Are there potential downsides to this idea? </div>
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<div>We are using <span>slony1-91-II-2.1.4 and Postgres 9.1 on RHEL 6, later we will most likely do the same type of migration from 9.1 to 9.5. </span></div>
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<div>Any response is greatly appreciated.</div>
<div>Thanks!</div>
<div>Zarko</div>
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