Persistent hash iRule

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1

Hi All,

I have a question regarding the Persistent hash iRule.

Two Pool members are configured as Round robin.

Sessions have been concentrated as one pool member since we added the Persistent hash iRule below to the virtual server.

There are two Client IPs in total and have not changed since iRule was applied.

What is the reason? Please help me.

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<Pool member#1 connection>

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<Pool member#2 connection>

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Thanks.

2

You calculate an MD5 hash over the IP Address and use the last 8 bit to determine what pool member to balance to?

With 2 poolmembers, it breaks down to if the hash is even or odd and with only 2 clients, chances are 50:50 that they’re both odd/even or different.