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Replication between 2 NAC Guest Access Servers

My question is on the NAC Guest Access Server:

1) Is there documentation stating that the Active/Active support Bi-directional replication of the database and that only when initiating the secondary for the first time causes the secondary device to be completely overwrittenwith the primary data?

2) The scenario is the there are 2 NGS's separated by WAN; What happens if the 2 devices cannot communicate for a period of time, say longer than 8 hours. How does reconciliation of the database take place?

Everyone's tags (3)
2 REPLIES
Cisco Employee

Re: Replication between 2 NAC Guest Access Servers

Hi,

High availability is provided in an active/active  scenario, where both Cisco NAC Guest Servers can service requests from  sponsors or network devices at the same time. This capability also  allows you to load balance the requests between the boxes.

All data on one of the Guest  Servers will be overwritten. If you have data that is needed on both  Guest Servers, then you should not configure replication as you will  lose data.

Once one of the Guest Servers has received a copy of the data from the  other device, they are synchronized and replication is turned on. Any  data that is updated on one Guest Server is then automatically  replicated to the other Guest Server.

The detailed info can be found here:

http://www.cisco.com/en/US/docs/security/nac/guestserver/configuration_guide/20/g_replication.html#wp1071617.

When the network connectivity between two Cisco  NAC Guest Servers fails, the Cisco NAC Guest Servers stores up to 1GB of  changes. When connectivity is restored, if the amount of changes is  less than 1GB, they will synchronize with each other. If more than 1GB  of changes are stored, the Cisco NAC Guest Server stops the replication  process and you need to setup replication again.

HTH,

Tiago

--

If  this helps you and/or answers your question please mark the question as  "answered" and/or rate it, so other users can easily find it.

Cisco Employee

Re: Replication between 2 NAC Guest Access Servers

Hi,

High availability is provided in an active/active  scenario, where both Cisco NAC Guest Servers can service requests from  sponsors or network devices at the same time. This capability also  allows you to load balance the requests between the boxes.

All data on one of the Guest  Servers will be overwritten. If you have data that is needed on both  Guest Servers, then you should not configure replication as you will  lose data.

Once one of the Guest Servers has received a copy of the data from the  other device, they are synchronized and replication is turned on. Any  data that is updated on one Guest Server is then automatically  replicated to the other Guest Server.

The detailed info can be found here:

http://www.cisco.com/en/US/docs/security/nac/guestserver/configuration_guide/20/g_replication.html#wp1071617.

When the network connectivity between two Cisco  NAC Guest Servers fails, the Cisco NAC Guest Servers stores up to 1GB of  changes. When connectivity is restored, if the amount of changes is  less than 1GB, they will synchronize with each other. If more than 1GB  of changes are stored, the Cisco NAC Guest Server stops the replication  process and you need to setup replication again.

HTH,

Tiago

--

If  this helps you and/or answers your question please mark the question as  "answered" and/or rate it, so other users can easily find it.

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