For some reason, it seems I am no longer receiving blockchain information from peers. When I tail the debug log file (e.g. tail -f /path/to/data/debug.log), this is what I see. Note that I have replaced the machine's internal and external IPs with w.x.y.z.

2017-03-22 01:01:45 socket send error Bad file descriptor (9)
2017-03-22 01:01:45 ProcessMessages(version, 102 bytes) FAILED peer=61
2017-03-22 01:03:13 connect() to [2001:0:34ad:4890:20d9:1be6:c114:2db8]:8333 failed: Network is unreachable (101)
2017-03-22 01:06:24 UpdateTip: new best=0000000000000000007e1cab699eba16af94e62c3c58bf8b38cc00793de83b25 height=458332 version=0x20000000 log2_work=86.161702 tx=206837725 date='2017-03-22 01:06:17' progress=1.000000 cache=218.2MiB(140090tx)
2017-03-22 01:12:45 UpdateTip: new best=0000000000000000000e7b4d72abdfbf7d0618627656ceac6ee0f81edcb51001 height=458333 version=0x20000000 log2_work=86.161736 tx=206840788 date='2017-03-22 01:12:22' progress=1.000000 cache=219.0MiB(143564tx)
2017-03-22 01:17:52 connect() to [2a00:23c4:4900:b100:6c09:9ca4:bbcc:50f7]:8333 failed: Network is unreachable (101)
2017-03-22 01:20:02 connect() to [2001:0:d5c:5a30:3828:1853:9c4b:b8f0]:8333 failed: Network is unreachable (101)
2017-03-22 01:22:25 connect() to 139.162.118.32:8333 failed after select(): Connection refused (111)
2017-03-22 01:23:13 connect() to 25.57.176.50:8333 failed after select(): Network is unreachable (101)
2017-03-22 01:23:14 connect() to [2001:0:34ac:b067:3482:d5f:a76c:d681]:8333 failed: Network is unreachable (101)
2017-03-22 01:24:47 AdvertiseLocal: advertising address w.x.y.z:8333
2017-03-22 01:25:41 ProcessMessages: advertising address w.x.y.z:8333
2017-03-22 01:25:41 receive version message: /Satoshi:0.14.0/: version 70015, blocks=458333, us=w.x.y.z:58092, peer=62
2017-03-22 01:25:41 AdvertiseLocal: advertising address w.x.y.z:8333
2017-03-22 01:27:30 connect() to 84.46.6.82:8333 failed after select(): No route to host (113)
2017-03-22 01:31:09 Pre-allocating up to position 0xd00000 in rev00810.dat
2017-03-22 01:31:09 UpdateTip: new best=0000000000000000009438446ed0a3d0a437a38a395d9893ba4b4dfa34b625e0 height=458334 version=0x20000000 log2_work=86.16177 tx=206843152 date='2017-03-22 01:30:11' progress=1.000000 cache=225.5MiB(147484tx)
2017-03-22 01:37:00 connect() to [2001:0:34af:cc99:3835:4ba:b1db:e61b]:8333 failed: Network is unreachable (101)
2017-03-22 01:40:15 connect() to [2601:681:4180:601:342e:58f4:5406:a2f1]:8333 failed: Network is unreachable (101)
2017-03-22 01:41:24 ProcessMessages: advertising address W.X.Y.Z:8333
2017-03-22 01:41:24 receive version message: /Satoshi:0.13.2/: version 70015, blocks=458334, us=W.X.Y.Z:56428, peer=63
2017-03-22 01:41:24 AdvertiseLocal: advertising address W.X.Y.Z:8333
2017-03-22 01:41:24 socket send error Bad file descriptor (9)
2017-03-22 01:44:52 Pre-allocating up to position 0x7000000 in blk00810.dat
2017-03-22 01:44:52 UpdateTip: new best=000000000000000001fcb4f772a0ccb44ae5cdcafb4af8b84546a3448db303a8 height=458335 version=0x20000000 log2_work=86.161804 tx=206845444 date='2017-03-22 01:44:02' progress=1.000000 cache=227.6MiB(151114tx)

When I type in netstat -anp | grep 8333 to see which peer nodes I'm connected to, I see the following.

tcp        0      0 0.0.0.0:8333                0.0.0.0:*                   LISTEN      16899/bitcoind      
tcp        0      0 w.x.y.z:46840          212.59.241.216:8333         ESTABLISHED 16899/bitcoind      
tcp        0      0 w.x.y.z:34346          5.9.94.12:8333              ESTABLISHED 16899/bitcoind      
tcp        0      0 w.x.y.z:54488          88.99.109.181:8333          ESTABLISHED 16899/bitcoind      
tcp        0      0 w.x.y.z:51256          150.95.145.61:8333          ESTABLISHED 16899/bitcoind      
tcp        0      0 w.x.y.z:33368          52.64.15.18:8333            ESTABLISHED 16899/bitcoind      
tcp        0      0 w.x.y.z:45634          213.93.10.185:8333          ESTABLISHED 16899/bitcoind      
tcp        0      0 w.x.y.z:42636          5.189.155.84:8333           ESTABLISHED 16899/bitcoind      
tcp        0      0 w.x.y.z:51966          163.172.55.147:8333         ESTABLISHED 16899/bitcoind      
tcp        0      0 :::8333                     :::*                        LISTEN      16899/bitcoind

When I type in netstat -anp | grep LISTEN I see the following.

tcp        0      0 127.0.0.1:25                0.0.0.0:*                   LISTEN      2521/sendmail       
tcp        0      0 w.x.y.z:28322          0.0.0.0:*                   LISTEN      16899/bitcoind      
tcp        0      0 0.0.0.0:50147               0.0.0.0:*                   LISTEN      2301/rpc.statd      
tcp        0      0 w.x.y.z:8332           0.0.0.0:*                   LISTEN      16899/bitcoind      
tcp        0      0 0.0.0.0:8333                0.0.0.0:*                   LISTEN      16899/bitcoind      
tcp        0      0 0.0.0.0:111                 0.0.0.0:*                   LISTEN      2280/rpcbind        
tcp        0      0 0.0.0.0:22                  0.0.0.0:*                   LISTEN      2491/sshd           
tcp        0      0 :::47559                    :::*                        LISTEN      2301/rpc.statd      
tcp        0      0 :::8333                     :::*                        LISTEN      16899/bitcoind      
tcp        0      0 :::111                      :::*                        LISTEN      2280/rpcbind        
tcp        0      0 :::22                       :::*                        LISTEN      2491/sshd           
unix  2      [ ACC ]     STREAM     LISTENING     8079   1/init              @/com/ubuntu/upstart
unix  2      [ ACC ]     SEQPACKET  LISTENING     8345   1530/udevd          @/org/kernel/udev/udevd
unix  2      [ ACC ]     STREAM     LISTENING     9945   2280/rpcbind        /var/run/rpcbind.sock
unix  2      [ ACC ]     STREAM     LISTENING     10117  2332/dbus-daemon    /var/run/dbus/system_bus_socket

When I use top to look at the CPU + MEM usage, they are at 3.3% and 24.2%, respectively.

I must say that only port 22 inbound is allowed, and all other ports are blocked. This full-node is sitting in an AWS EC2 instance. But I don't think this setup is really the problem because a while back, I was getting blockchain data.

The way I start the daemon is as follows: bitcoind -datadir=/path/to/data -daemon.

My bitcoin.conf file looks like the following.

rpcpassword=somepassword
rpcbind=w.x.y.z
rpcallowip=w.x.y.z/24
rpcallowip=v.x.y.z/24
zmqpubhashtx=tcp://w.x.y.z:28322
zmqpubhashblock=tcp://w.x.y.z:28322
zmqpubrawblock=tcp://w.x.y.z:28322
zmqpubrawtx=tcp://w.x.y.z:28322
txindex=1

Here's the result for bitcoin-cli getinfo.

{
  "version": 130200,
  "protocolversion": 70015,
  "walletversion": 130000,
  "balance": 0.00000000,
  "blocks": 458338,
  "timeoffset": 0,
  "connections": 8,
  "proxy": "",
  "difficulty": 475705205061.6292,
  "testnet": false,
  "keypoololdest": 1488865612,
  "keypoolsize": 100,
  "paytxfee": 0.00000000,
  "relayfee": 0.00001000,
  "errors": ""
}

A command for checking errors in the log cat /path/to/data/debug.log | grep error shows the following messages.

2017-03-20 11:37:30 socket send error Bad file descriptor (9)
2017-03-21 00:45:39 socket recv error Connection reset by peer (104)
2017-03-21 01:01:24 socket recv error Connection timed out (110)

Any idea on what's wrong?

Should I be allowing more peer connections? I've read in several places that I should NOT be connecting to more than 8 peers (the default) since I am only capturing transaction data and also increasing the peers might take away propagation resources/nodes in the global network.

Could it be the peers that I'm connected to (that they are unreliable)?

Any help is appreciated.