# Gateway master db\_tag

**URL:** <https://forum.inductiveautomation.com/t/gateway-master-db-tag/3398>\
**Category:** Ignition\
**Created:** [October 6, 2011, 10:20pm UTC](https://forum.inductiveautomation.com/t/gateway-master-db-tag/3398 "2011-10-06T22:20:10Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Henry](https://avatars.discourse-cdn.com/v4/letter/h/df705f/32.png) [@Henry](https://forum.inductiveautomation.com/u/Henry)\
**Post date:** [October 6, 2011, 10:20pm UTC](https://forum.inductiveautomation.com/t/gateway-master-db-tag/3398/1 "2011-10-06T22:20:10Z")

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Is it possible to create a database tag that can be logged and tells me which gateway system is acting as the master?

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**Author:** ![diat150](https://avatars.discourse-cdn.com/v4/letter/d/a587f6/32.png) [@diat150](https://forum.inductiveautomation.com/u/diat150)\
**Post date:** [October 6, 2011, 11:42pm UTC](https://forum.inductiveautomation.com/t/gateway-master-db-tag/3398/2 "2011-10-06T23:42:36Z")

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I have a gateway timer script that runs every 30 seconds or something

```auto

from java.net import InetAddress
nodename = InetAddress.getLocalHost().getHostName() 
if nodename == 'SCDAPOL1':
	system.tag.writeToTag('NodeName', nodename)
elif nodename == 'SCDAPOL2': 
         system.tag.writeToTag('NodeName', nodename)

```

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<div class="post-metadata">

**Author:** ![Robert.McKenzie](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/robert.mckenzie/32/4134_2.png) [@Robert.McKenzie](https://forum.inductiveautomation.com/u/Robert.McKenzie)\
**Post date:** [October 7, 2011, 4:37pm UTC](https://forum.inductiveautomation.com/t/gateway-master-db-tag/3398/3 "2011-10-07T16:37:02Z")

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There is a system tag for this in 7.3.0, you can use this code:`#assuming the master node is SCDAPOL1
master = system.tag.getTagValue("[System]Gateway/Redundancy/IsMaster")
if master:
   system.tag.writeToTag('NodeName', 'SCDAPOL1')
else:
   system.tag.writeToTag('NodeName', 'SCDAPOL2')`Or better yet, just use an expression:`if({[System]Gateway/Redundancy/IsMaster},"SCDAPOL1","SCDAPOL2")`

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<div class="post-metadata">

**Author:** ![Henry](https://avatars.discourse-cdn.com/v4/letter/h/df705f/32.png) [@Henry](https://forum.inductiveautomation.com/u/Henry)\
**Post date:** [October 7, 2011, 10:18pm UTC](https://forum.inductiveautomation.com/t/gateway-master-db-tag/3398/4 "2011-10-07T22:18:47Z")

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Works great!

Thank you