There seems to be some issue with the /dev/sda disk on the cloudelastic1004.wikimedia.org server:
aborrero@cloudelastic1004:~ $ sudo smartctl -H /dev/sda smartctl 6.6 2016-05-31 r4324 [x86_64-linux-4.9.0-7-amd64] (local build) Copyright (C) 2002-16, Bruce Allen, Christian Franke, www.smartmontools.org === START OF READ SMART DATA SECTION === SMART overall-health self-assessment test result: FAILED! Drive failure expected in less than 24 hours. SAVE ALL DATA. Failed Attributes: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 201 Unknown_SSD_Attribute 0x0033 001 001 010 Pre-fail Always FAILING_NOW 163735568957
Disk may need replacement. Netbox link: https://netbox.wikimedia.org/dcim/devices/266/