Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.89) (envelope-from ) id 1er3YV-0003kJ-Jv for pgsql-admin@arkaria.postgresql.org; Wed, 28 Feb 2018 15:22:07 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.89) (envelope-from ) id 1er3YU-00015C-7m for pgsql-admin@arkaria.postgresql.org; Wed, 28 Feb 2018 15:22:06 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.89) (envelope-from ) id 1er3YU-000151-0W for pgsql-admin@lists.postgresql.org; Wed, 28 Feb 2018 15:22:06 +0000 Received: from omr1.cc.ipv6.vt.edu ([2607:b400:92:8300:0:c6:2117:b0e] helo=omr1.cc.vt.edu) by magus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.89) (envelope-from ) id 1er3YM-0002qq-91 for pgsql-admin@postgresql.org; Wed, 28 Feb 2018 15:22:05 +0000 Received: from mr1.cc.vt.edu (mail.ipv6.vt.edu [IPv6:2607:b400:92:9:0:9d:8fcb:4116]) by omr1.cc.vt.edu (8.14.4/8.14.4) with ESMTP id w1SFLs6o006614 for ; Wed, 28 Feb 2018 10:21:54 -0500 Received: from mail-qt0-f197.google.com (mail-qt0-f197.google.com [209.85.216.197]) by mr1.cc.vt.edu (8.14.7/8.14.7) with ESMTP id w1SFLnkS020994 for ; Wed, 28 Feb 2018 10:21:54 -0500 Received: by mail-qt0-f197.google.com with SMTP id l32so2283291qtd.2 for ; Wed, 28 Feb 2018 07:21:54 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=xkAmb2NSs9IMwvbFOCCuGdil+xKJMPzL2dHMWgGvorg=; b=mjhMepVV70QPO45ApCDltP7Fiob028mdaDgeiBYR1Kjxd+R08V9G+5poVRAASa1isN PGkLnx/kX9a63X6M/VpQaHsgCmg1EpCMt6PcK3U9iijkZxP2hnPZZ2GbWlQoSnwyJESe 7mWlHFsWpiZvrMKTApGHwqX9U3nfzH4bZNffHGJpOyYJXU6bB73X+mZ5RUvXQS4t7V1p 6ZtmvmjW59mWhbAZrfHBetO0hohSczYIQp5Dejh4MGJ3BFoU/C9POrc5vb6kYURBrTVw +FJxqM0qJCGAisjpfW/k2Z9HvxYQZqKGsnTx3DzZ1zxlFLZPZ4u4Z9kB4UX9Lz3tBLmb 8LJQ== X-Gm-Message-State: APf1xPCFTW/wnIUBa7Ju2+xKpK6/B8Y57Qa+Eeq0uSVR6foLarMW8+98 07Yfe8C++7lyPYlRDhc6bagpUqaFVTE//76iSY61nvNpLDJhM++ZnVP1ahRJVOlUfbHTFA1fQga HSk3ObqqE66uNfJg6RN95JXL8m5FtEJhKmKMRyImcoXPQpvv0uQrTQi3jwh4YbLi606yT/T2f+C me X-Received: by 10.55.126.69 with SMTP id z66mr27496923qkc.218.1519831308668; Wed, 28 Feb 2018 07:21:48 -0800 (PST) X-Google-Smtp-Source: AG47ELtpmI0xlItnIDakhEQxPke2NyW+c4V0Lj2IqOnGCGzwq97Al5Kd8K2SOwD76hv5OiJSNe8dpQ== X-Received: by 10.55.126.69 with SMTP id z66mr27496905qkc.218.1519831308444; Wed, 28 Feb 2018 07:21:48 -0800 (PST) Received: from stell.cns.vt.edu ([2001:468:c80:2102:d05b:8969:3c7c:2842]) by smtp.gmail.com with ESMTPSA id l80sm1197053qki.92.2018.02.28.07.21.47 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 28 Feb 2018 07:21:47 -0800 (PST) Subject: Re: Reliable WAL file shipping over unreliable network To: =?UTF-8?Q?Nagy_L=c3=a1szl=c3=b3_Zsolt?= , pgsql-admin@postgresql.org References: From: Ray Stell Message-ID: <3c9f0338-631c-ed8f-a7a1-e1bf7d69b4a7@vt.edu> Date: Wed, 28 Feb 2018 10:21:47 -0500 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=iso-8859-2; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Precedence: bulk On 2/28/18 9:57 AM, Nagy László Zsolt wrote: > but > am I right in that I can combine log file shipping with streaming > replication, and achieve small replication delays plus the ability to > recover after a longer period if network outage? > yes. You might look at adjusting your wal_keep_segments to retain WAL for a period longer than expected network failures.  This might require some storage planning/adjustments.