2017-12-01

• Uptime Robot noticed that CGSpace went down
• The logs say "Timeout waiting for idle object"
• PostgreSQL activity says there are 115 connections currently
• The list of connections to XMLUI and REST API for today:

# cat /var/log/nginx/rest.log  /var/log/nginx/rest.log.1  /var/log/nginx/access.log /var/log/nginx/access.log.1 /var/log/nginx/library-access.log /var/log/nginx/library-access.log.1 | grep -E "1/Dec/2017" | awk '{print $1}' | sort -n | uniq -c | sort -h | tail
    763 2.86.122.76
    907 207.46.13.94
   1018 157.55.39.206
   1021 157.55.39.235
   1407 66.249.66.70
   1411 104.196.152.243
   1503 50.116.102.77
   1805 66.249.66.90
   4007 70.32.83.92
   6061 45.5.184.196

• The number of DSpace sessions isn't even that high:

$ cat /home/cgspace.cgiar.org/log/dspace.log.2017-12-01 | grep -o -E 'session_id=[A-Z0-9]{32}' | sort -n | uniq | wc -l
5815

• Connections in the last two hours:

# cat /var/log/nginx/rest.log  /var/log/nginx/rest.log.1  /var/log/nginx/access.log /var/log/nginx/access.log.1 /var/log/nginx/library-access.log /var/log/nginx/library-access.log.1 | grep -E "1/Dec/2017:(09|10)" | awk '{print $1}' | sort -n | uniq -c | sort -h | tail                                                      
     78 93.160.60.22
    101 40.77.167.122
    113 66.249.66.70
    129 157.55.39.206
    130 157.55.39.235
    135 40.77.167.58
    164 68.180.229.254
    177 87.100.118.220
    188 66.249.66.90
    314 2.86.122.76

• What the fuck is going on?
• I've never seen this 2.86.122.76 before, it has made quite a few unique Tomcat sessions today:

$ grep 2.86.122.76 /home/cgspace.cgiar.org/log/dspace.log.2017-12-01 | grep -o -E 'session_id=[A-Z0-9]{32}' | sort -n | uniq | wc -l
822

• Appears to be some new bot:

2.86.122.76 - - [01/Dec/2017:09:02:53 +0000] "GET /handle/10568/78444?show=full HTTP/1.1" 200 29307 "-" "Mozilla/3.0 (compatible; Indy Library)"

• I restarted Tomcat and everything came back up
• I can add Indy Library to the Tomcat crawler session manager valve but it would be nice if I could simply remap the useragent in nginx
• I will also add 'Drupal' to the Tomcat crawler session manager valve because there are Drupals out there harvesting and they should be considered as bots

# cat /var/log/nginx/rest.log  /var/log/nginx/rest.log.1  /var/log/nginx/access.log /var/log/nginx/access.log.1 /var/log/nginx/library-access.log /var/log/nginx/library-access.log.1 | grep -E "1/Dec/2017" | grep Drupal | awk '{print $1}' | sort -n | uniq -c | sort -h | tail
      3 54.75.205.145
      6 70.32.83.92
     14 2a01:7e00::f03c:91ff:fe18:7396
     46 2001:4b99:1:1:216:3eff:fe2c:dc6c
    319 2001:4b99:1:1:216:3eff:fe76:205b

2017-12-03

• Linode alerted that CGSpace's load was 327.5% from 6 to 8 AM again

2017-12-04

• Linode alerted that CGSpace's load was 255.5% from 8 to 10 AM again
• I looked at the Munin stats on DSpace Test (linode02) again to see how the PostgreSQL tweaks from a few weeks ago were holding up:

• The results look fantastic! So the random_page_cost tweak is massively important for informing the PostgreSQL scheduler that there is no "cost" to accessing random pages, as we're on an SSD!
• I guess we could probably even reduce the PostgreSQL connections in DSpace / PostgreSQL after using this
• Run system updates on DSpace Test (linode02) and reboot it
• I'm going to enable the PostgreSQL random_page_cost tweak on CGSpace
• For reference, here is the past month's connections:

2017-12-05

• Linode alerted again that the CPU usage on CGSpace was high this morning from 8 to 10 AM
• CORE updated the entry for CGSpace on their index: https://core.ac.uk/search?q=repositories.id:(1016)&fullTextOnly=false
• Linode alerted again that the CPU usage on CGSpace was high this evening from 8 to 10 PM

2017-12-06

• Linode alerted again that the CPU usage on CGSpace was high this morning from 6 to 8 AM
• Uptime Robot alerted that the server went down and up around 8:53 this morning
• Uptime Robot alerted that CGSpace was down and up again a few minutes later
• I don't see any errors in the DSpace logs but I see in nginx's access.log that UptimeRobot was returned with HTTP 499 status (Client Closed Request)
• Looking at the REST API logs I see some new client IP I haven't noticed before:

# cat /var/log/nginx/rest.log /var/log/nginx/rest.log.1 | grep -E "6/Dec/2017" | awk '{print $1}' | sort -n | uniq -c | sort -h | tail
     18 95.108.181.88
     19 68.180.229.254
     30 207.46.13.151
     33 207.46.13.110
     38 40.77.167.20
     41 157.55.39.223
     82 104.196.152.243
   1529 50.116.102.77
   4005 70.32.83.92
   6045 45.5.184.196

• 50.116.102.77 is apparently in the US on websitewelcome.com

2017-12-07

• Uptime Robot reported a few times today that CGSpace was down and then up
• At one point Tsega restarted Tomcat
• I never got any alerts about high load from Linode though...
• I looked just now and see that there are 121 PostgreSQL connections!
• The top users right now are:

# cat /var/log/nginx/access.log /var/log/nginx/access.log.1 /var/log/nginx/library-access.log /var/log/nginx/library-access.log.1 | grep -E "7/Dec/2017" | awk '{print $1}' | sort -n | uniq -c | sort -h | tail 
    838 40.77.167.11
    939 66.249.66.223
   1149 66.249.66.206
   1316 207.46.13.110
   1322 207.46.13.151
   1323 2001:da8:203:2224:c912:1106:d94f:9189
   1414 157.55.39.223
   2378 104.196.152.243
   2662 66.249.66.219
   5110 124.17.34.60

• We've never seen 124.17.34.60 yet, but it's really hammering us!
• Apparently it is from China, and here is one of its user agents:

Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.2; Win64; x64; Trident/7.0; LCTE)

• It is responsible for 4,500 Tomcat sessions today alone:

$ grep 124.17.34.60 /home/cgspace.cgiar.org/log/dspace.log.2017-12-07 | grep -o -E 'session_id=[A-Z0-9]{32}' | sort -n | uniq | wc -l
4574

• I've adjusted the nginx IP mapping that I set up last month to account for 124.17.34.60 and 124.17.34.59 using a regex, as it's the same bot on the same subnet
• I was running the DSpace cleanup task manually and it hit an error:

$ /home/cgspace.cgiar.org/bin/dspace cleanup -v
...
Error: ERROR: update or delete on table "bitstream" violates foreign key constraint "bundle_primary_bitstream_id_fkey" on table "bundle"
  Detail: Key (bitstream_id)=(144666) is still referenced from table "bundle".

• The solution is like I discovered in 2017-04, to set the primary_bitstream_id to null:

dspace=# update bundle set primary_bitstream_id=NULL where primary_bitstream_id in (144666);
UPDATE 1

2017-12-13

• Linode alerted that CGSpace was using high CPU from 10:13 to 12:13 this morning