Checking Node Status

Process Status

It is possible to check the status of SCN's process using the status commands systemctl and kscnd.

systemctl

systemctl is installed along with the RPM, and the status of SCN can be checked as follows.

$ systemctl status kscnd.service
● kscnd.service - (null)
   Loaded: loaded (/etc/rc.d/init.d/kscnd; bad; vendor preset: disabled)
   Active: active (running) since Wed 2019-01-09 11:42:39 UTC; 1 months 4 days ago
     Docs: man:systemd-sysv-generator(8)
  Process: 29636 ExecStart=/etc/rc.d/init.d/kscnd start (code=exited, status=0/SUCCESS)
 Main PID: 29641 (kscn)
   CGroup: /system.slice/kscnd.service
           └─29641 /usr/local/bin/kscn --networkid 1000 --datadir ~/kscnd_home --port 32323 --srvtype fasthttp --metrics --prometheus --verbosity 3 --txpool.global...

Jan 09 11:42:39 ip-10-11-2-101.ap-northeast-2.compute.internal systemd[1]: Starting (null)...
Jan 09 11:42:39 ip-10-11-2-101.ap-northeast-2.compute.internal kscnd[29636]: Starting kscnd: [  OK  ]
Jan 09 11:42:39 ip-10-11-2-101.ap-northeast-2.compute.internal systemd[1]: Started (null).

You can check the current status such as Active: active (running) in the example above.

kscnd

kscnd is installed along with the package, and the status of SCN can be checked as follows.

$ kscnd status
kscnd is running

Logs

The log is stored in kscnd.out file located in the path defined in the LOG_DIR field of the kscnd.conf file. When the node works properly, you can see that each block is imported per second as follows.

Example:

$ tail -F ~/kscnd_home/logs/kscnd.out
  INFO[11/12,10:19:09 +09] [49] Successfully wrote mined block            num=11 hash=03da06…f194b0 txs=0
  INFO[11/12,10:19:09 +09] [49] Commit new mining work                    number=12 txs=0 elapsed=236.972µs
  INFO[11/12,10:19:10 +09] [24] Committed                                 number=12 hash=470aca…be4fdf address=0xf8690562c0839C44B17AF421F7AaaA9F12dCc62b
  INFO[11/12,10:19:10 +09] [49] Successfully sealed new block             number=12 hash=470aca…be4fdf
  INFO[11/12,10:19:10 +09] [49] Successfully wrote mined block            num=12 hash=470aca…be4fdf txs=0
  INFO[11/12,10:19:10 +09] [49] Commit new mining work                    number=13 txs=0 elapsed=198.221µs
  INFO[11/12,10:19:11 +09] [24] Committed                                 number=13 hash=95e4a3…14e50f address=0xf8690562c0839C44B17AF421F7AaaA9F12dCc62b
  INFO[11/12,10:19:11 +09] [49] Successfully sealed new block             number=13 hash=95e4a3…14e50f
  INFO[11/12,10:19:11 +09] [49] Successfully wrote mined block            num=13 hash=95e4a3…14e50f txs=0
  INFO[11/12,10:19:11 +09] [49] Commit new mining work                    number=14 txs=0 elapsed=220.004µs
  INFO[11/12,10:19:12 +09] [24] Committed                                 number=14 hash=dcd2bc…b2aec0 address=0xf8690562c0839C44B17AF421F7AaaA9F12dCc62b

Queries

kscn console

Klaytn provides a CLI client: kscn console. Another way of using the client is to connect to the process via IPC (inter-process communication). The IPC file klay.ipc is located in the data directory on an SCN.

Please execute the following command and check out the result.

$ kscn attach ~/kscnd_home/klay.ipc
Welcome to the Klaytn JavaScript console!

instance: Klaytn/vX.X.X/XXXX-XXXX/goX.X.X
at block: 11573551 (Wed, 13 Feb 2019 07:12:52 UTC)
 datadir: ~/kscnd_home
 modules: admin:1.0 debug:1.0 istanbul:1.0 klay:1.0 miner:1.0 net:1.0 personal:1.0 rpc:1.0 txpool:1.0
 >

You can check the usable commands on API Document

The useful APIs to check the status of SCN:

• klay.blockNumber (to get the latest block number)

• net.peerCount (to get the number of the connected Klaytn nodes currently)

klay.blockNumber

You can get the latest block number to see if blocks are propagated properly.

> klay.blockNumber
11573819

net.peerCount

> net.peerCount
4

The above command line returns the number of nodes that the SCN connects to except the EN in the main chain.