From ce9af413ca4317ee42a472585afe8d6a0def4a74 Mon Sep 17 00:00:00 2001 From: Bob Grabar Date: Tue, 18 Dec 2012 23:15:58 -0500 Subject: [PATCH 1/2] DOCS-693 migrate Troubleshooting page --- source/faq/fundamentals.txt | 45 +++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) diff --git a/source/faq/fundamentals.txt b/source/faq/fundamentals.txt index 58915510640..f9a96ed4b63 100644 --- a/source/faq/fundamentals.txt +++ b/source/faq/fundamentals.txt @@ -222,3 +222,48 @@ operating systems are strongly recommended. 32-bit builds disable :term:`journaling ` by default because journaling further limits the maximum amount of data that the database can store. + +.. todo Create a Troubleshooting page for these next two faqs on + shutdowns and keepalive + +The ``mongod`` process has disappeared from the logs. Where can I find information? +----------------------------------------------------------------------------------- + +If :program:`mongod` shuts down unexpectedly on a UNIX or UNIX-based +platform, and if :program:`mongod` fails to log a shutdown or error +message, then check the global logs in the ``/var/log/messages`` +directory. Check for messages pertaining to MongoDB by running the +following commands: + +.. code-block:: sh + + sudo grep mongod /var/log/messages + sudo grep score /var/log/messages + +Does TCP "keepalive" time affect sharded clusters and replica sets? +------------------------------------------------------------------- + +If you are experiencing unexplainable socket errors between members of a +sharded cluster or replica set, check the ``tcp_keepalive_time`` value. +The default Linux ``tcp_keepalive_time`` value is ``7200`` seconds (2 +hours). For MongoDB, change this to ``300`` seconds (five minutes). + +To check your ``tcp_keepalive_time`` value, issue the following command: + +.. code-block:: sh + + cat /proc/sys/net/ipv4/tcp_keepalive_time + +To change the ``tcp_keepalive_time`` value, issue the following command: + +.. code-block:: sh + + echo 300 > /proc/sys/net/ipv4/tcp_keepalive_time + +The new ``tcp_keepalive_time`` value takes effect without requiring you +to restart not need to restart the :program:`mongod` or +:program:`mongos` servers. + +You must alter the ``tcp_keepalive_time`` value on all machines hosting +MongoDB processes. This includes all machines hosting :program:`mongos` +or :program:`mongod` servers. From f96bf748439f4fd38a32a4401ecd347de5c7b477 Mon Sep 17 00:00:00 2001 From: Bob Grabar Date: Thu, 20 Dec 2012 18:52:39 -0500 Subject: [PATCH 2/2] DOCS-693 edits --- source/faq/fundamentals.txt | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/source/faq/fundamentals.txt b/source/faq/fundamentals.txt index f9a96ed4b63..996b6c09ea4 100644 --- a/source/faq/fundamentals.txt +++ b/source/faq/fundamentals.txt @@ -231,9 +231,9 @@ The ``mongod`` process has disappeared from the logs. Where can I find informati If :program:`mongod` shuts down unexpectedly on a UNIX or UNIX-based platform, and if :program:`mongod` fails to log a shutdown or error -message, then check the global logs in the ``/var/log/messages`` -directory. Check for messages pertaining to MongoDB by running the -following commands: +message, then check your system logs for messages pertaining to MongoDB. +For example, if the logs are located in ``/var/log/messages``, +run the following commands: .. code-block:: sh @@ -261,7 +261,7 @@ To change the ``tcp_keepalive_time`` value, issue the following command: echo 300 > /proc/sys/net/ipv4/tcp_keepalive_time The new ``tcp_keepalive_time`` value takes effect without requiring you -to restart not need to restart the :program:`mongod` or +to restart the :program:`mongod` or :program:`mongos` servers. You must alter the ``tcp_keepalive_time`` value on all machines hosting