UM Active/Active cluster

, ,
1

Hello

1-st, apologies for my english…

I’m facing a problem with creating an Active/Active cluster :?

My UM servers are installed on Linux, and they are "fixed"with FIX 9 :slight_smile: (attached screenshots)

When i try to use them as standalone UM servers its ok, my IS is “talking” with them.

but when it comes to cluster creation, problems apear

By the numbers:

  1. connecting with Ent Manager (installed on my PC - Win7, fixed with FIX 10 ) to all 3 instances: esbum1, esbum2, esbum3 - ok
  2. all instances have no channels, etc. - ok
  3. creating cluster - adding esbum1, esbum2, esbum3 as nodes , then OK - still ok
  4. in Cluster Summary window no info about connecting between nodes in cluster - NOT ok

In Cluster Logfile tab only message repeating constantly:
esbum2:>[Wed May 25 11:39:45 CEST 2016],Cluster> Setting potential master to esbum2 yet master count is only 1.0 while we we need more than 1.0 for quorum
esbum2:>[Wed May 25 11:39:45 CEST 2016],Cluster> Setting potential master to esbum2 yet master count is only 1.0 while we we need more than 1.0 for quorum
esbum3:>[Wed May 25 11:39:45 CEST 2016],Cluster> Setting potential master to esbum3 yet master count is only 1.0 while we we need more than 1.0 for quorum
esbum3:>[Wed May 25 11:39:45 CEST 2016],Cluster> Setting potential master to esbum3 yet master count is only 1.0 while we we need more than 1.0 for quorum
esbum2:>[Wed May 25 11:39:45 CEST 2016],Cluster> Setting potential master to esbum2 yet master count is only 1.0 while we we need more than 1.0 for quorum
esbum2:>[Wed May 25 11:39:45 CEST 2016],Cluster> Setting potential master to esbum2 yet master count is only 1.0 while we we need more than 1.0 for quorum
esbum3:>[Wed May 25 11:39:47 CEST 2016],Cluster> Setting potential master to esbum3 yet master count is only 1.0 while we we need more than 1.0 for quorum
esbum3:>[Wed May 25 11:39:47 CEST 2016],Cluster> Setting potential master to esbum3 yet master count is only 1.0 while we we need more than 1.0 for quorum
esbum2:>[Wed May 25 11:39:47 CEST 2016],Cluster> Setting potential master to esbum2 yet master count is only 1.0 while we we need more than 1.0 for quorum
esbum2:>[Wed May 25 11:39:47 CEST 2016],Cluster> Setting potential master to esbum2 yet master count is only 1.0 while we we need more than 1.0 for quorum

Any help apreciated :slight_smile:

EM cluster.png
EM cluster.png1280×768 111 KB

ums fix.png
ums fix.png1160×941 168 KB

EM cluster log.png
EM cluster log.png1280×768 226 KB

2

ok, found solution…

it turned out that linux servers couldn’t connect between each other beacuse UM on each server knew other nodes by name, not by ip:

found in realms.nst file of the UM config directory

realms/nodes were described by name used during install SofwareAG - eg. p032107esbum1.net.xx

so after adding names with IP addresses to hosts file cluster entered into online state

so problem was name resolution

to avoid this kind of problems, better add server names (used during install SAG) to dns