<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="">I have been reminded by a co-worker that we also found and fixed an issue <div class="">between delayed-ack and failover recently. This patch has not been released yet.</div><div class="">So in addition to migrating to a more recent version you may want to disable</div><div class="">delayed-ack for the time being.</div><div class=""><br class=""></div><div class="">regards,</div><div class="">Shawn</div><div class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Jun 29, 2015, at 10:17 AM, de Brouwer Tom (ST-CO/ENG5.1) <<a href="mailto:Tom.deBrouwer@nl.bosch.com" class="">Tom.deBrouwer@nl.bosch.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="WordSection1" style="page: WordSection1; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">Thanks. I will do that.<o:p class=""></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class=""> </span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">Would these fixes from 4.2 / 4.3 have been merged into 4.1-R11, or is that something I should have a look at myself?<o:p class=""></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class=""> </span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class="">Thanks again!<o:p class=""></o:p></span></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif; color: rgb(31, 73, 125);" class=""> </span></div><div class=""><div style="border-style: solid none none; border-top-color: rgb(181, 196, 223); border-top-width: 1pt; padding: 3pt 0cm 0cm;" class=""><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><b class=""><span style="font-size: 10pt; font-family: Tahoma, sans-serif;" class="">From:</span></b><span style="font-size: 10pt; font-family: Tahoma, sans-serif;" class=""><span class="Apple-converted-space"> </span><a href="mailto:dhcp-users-bounces@lists.isc.org" style="color: purple; text-decoration: underline;" class="">dhcp-users-bounces@lists.isc.org</a><span class="Apple-converted-space"> </span>[<a href="mailto:dhcp-users-bounces@lists.isc.org" style="color: purple; text-decoration: underline;" class="">mailto:dhcp-users-bounces@lists.isc.org</a>]<span class="Apple-converted-space"> </span><b class="">On Behalf Of<span class="Apple-converted-space"> </span></b>Shawn Routhier<br class=""><b class="">Sent:</b><span class="Apple-converted-space"> </span>maandag 29 juni 2015 18:30<br class=""><b class="">To:</b><span class="Apple-converted-space"> </span>Users of ISC DHCP<br class=""><b class="">Subject:</b><span class="Apple-converted-space"> </span>Re: DHCP server balancing issue<o:p class=""></o:p></span></div></div></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div><div class=""><blockquote style="margin-top: 5pt; margin-bottom: 5pt;" class=""><div class=""><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class="">On Jun 29, 2015, at 8:46 AM, Gregory Sloop <<a href="mailto:gregs@sloop.net" style="color: purple; text-decoration: underline;" class="">gregs@sloop.net</a>> wrote:<o:p class=""></o:p></div></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div><div class=""><div class=""><p class="MsoNormal" style="margin: 0cm 0cm 12pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><br class=""><br class=""><o:p class=""></o:p></p><table class="MsoNormalTable" border="0" cellpadding="0"><tbody class=""><tr class=""><td width="2" style="width: 1.5pt; background-color: blue; padding: 0.75pt; background-position: initial initial; background-repeat: initial initial;" class=""></td><td style="padding: 0.75pt;" class=""><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><span style="font-size: 11pt; font-family: Calibri, sans-serif;" class="">Hi,<br class=""><br class="">I’m experiencing some issues with my redundant ISC DHCP setup, I’m using version “dhcp-4.1-ESV-R4”, compiled with “--enable-delayed-ack”.<br class=""><br class="">The issue I’m experiencing is that the balancing suddenly stops and never restores correctly, and a such only half of my clients get IP addresses assigned. I debugged this currently to the stage that one of the DHCP servers get’s into the “communications-interrupted” state and therefore does not allow to balance the pool (I think). Sometimes it takes 2 weeks, sometime a few days before the servers gets into this state. Restarting dhcpd resolves this issue.<br class=""><br class="">In the slave log, I get the warning “Got POOLREQ, answering negatively! Peer may be out of leases or database inconsistent.”<br class=""><br class="">In the master log, I get the warning ”pool response: 0 leases”<br class=""><br class="">Under normal operations I see the master logging “balancing pool 8fe8f68 192.168.6.0/24 total 241 free 20 backup 81 lts -30 max-own (+/-)10” every hour, once I start experiencing this issue the log is changed into “balancing pool 8fe8f68 192.168.6.0/24 total 241 free 19 backup 81 lts -31 max-own (+/-)10 (requesting peer rebalance!)” Which I think means it gets to a critical available lease threshold.<span class="Apple-converted-space"> </span><br class=""><br class="">What could be causing this issue? I couldn’t find anything in the release notes of dhcp-4.1-ESV-R11 which explicitly points to this issue, so I’m not sure whether upgrading makes sense.<br class=""><br class="">Thanks,<br class=""><br class="">Tom</span><o:p class=""></o:p></div></td></tr></tbody></table><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><br class=""><br class=""><span style="font-size: 9pt; font-family: 'Courier New';" class="">I believe there are a number of load-balancing/fail-over bugs/corner-cases in 4.1 versions that are fixed in 4.2 and newer.</span><o:p class=""></o:p></div></div></div></blockquote><div class=""><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class="">Most bugs are generally fixed in all current releases. We have fixed several failover issues in more recent 4.1 as well as 4.2 or 4.3.<o:p class=""></o:p></div></div><div class=""><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class="">Some of the items we fixed could have odd results, if you are having issues with failover upgrading to R11 is a good idea.<o:p class=""></o:p></div></div><div class=""><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><br class=""><br class=""><o:p class=""></o:p></div><div class=""><div class=""><p class="MsoNormal" style="margin: 0cm 0cm 12pt; font-size: 12pt; font-family: 'Times New Roman', serif;"><span style="font-size: 9pt; font-family: 'Courier New';" class=""><br class="">You might do a search of the archives and see if you can find someone talking about them, but IIRC, they exist and are hard to nail down and, again IIRC, the "solution" I've seen is "try something more current." (i.e. 4.2+)<br class=""><br class="">HTH<br class=""><br class="">-Greg</span><o:p class=""></o:p></p></div></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div></div><div class=""><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class="">regards,<o:p class=""></o:p></div></div><div class=""><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class="">Shawn<o:p class=""></o:p></div></div><div style="margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: 'Times New Roman', serif;" class=""><o:p class=""> </o:p></div></div><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">_______________________________________________</span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">dhcp-users mailing list</span><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><a href="mailto:dhcp-users@lists.isc.org" style="color: purple; text-decoration: underline; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class="">dhcp-users@lists.isc.org</a><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><a href="https://lists.isc.org/mailman/listinfo/dhcp-users" style="color: purple; text-decoration: underline; font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class="">https://lists.isc.org/mailman/listinfo/dhcp-users</a></div></blockquote></div><br class=""></div></body></html>