# Aerospike C# Client gave error Error -8: Failed to resolve

**URL:** <https://discuss.aerospike.com/t/aerospike-c-client-gave-error-error-8-failed-to-resolve/6211>\
**Category:** C# Client\
**Created:** [April 30, 2019, 4:44pm UTC](https://discuss.aerospike.com/t/aerospike-c-client-gave-error-error-8-failed-to-resolve/6211 "2019-04-30T16:44:05Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![abhisheikh\_parihar](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.aerospike.com/abhisheikh_parihar/32/1076_2.png) [@abhisheikh\_parihar](https://discuss.aerospike.com/u/abhisheikh_parihar)\
**Post date:** [April 30, 2019, 4:44pm UTC](https://discuss.aerospike.com/t/aerospike-c-client-gave-error-error-8-failed-to-resolve/6211/1 "2019-04-30T16:44:05Z")

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Hi We are facing an issue with aerospike c# client in which if there is a burst of request(not more then 200 concurrent requests) aerospike client is giving us below mentioned error

```auto
Aerospike.Client.AerospikeException+Connection: Error -8: Failed to connect to host(s)URLS Error -8: Failed to resolve URLS at Aerospike.Client.Cluster.SeedNodes(Boolean failIfNotConnected)
   at Aerospike.Client.Cluster.Tend(Boolean failIfNotConnected)
   at Aerospike.Client.Cluster.WaitTillStabilized(Boolean failIfNotConnected)
   at Aerospike.Client.Cluster.InitTendThread(Boolean failIfNotConnected)
   at Aerospike.Client.AsyncClient..ctor(AsyncClientPolicy policy, Host[] hosts)

```

Note: Actual url are replaced by URLS

Please suggest what we are missing here,

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**Author:** ![Brian](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.aerospike.com/brian/32/2211_2.png) [@Brian](https://discuss.aerospike.com/u/Brian)\
**Post date:** [April 30, 2019, 5:12pm UTC](https://discuss.aerospike.com/t/aerospike-c-client-gave-error-error-8-failed-to-resolve/6211/2 "2019-04-30T17:12:49Z")

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This error occurs at startup when attempting to contact a seed node and the DNS lookup fails on the URL. The URL is not accessible from your client machine.

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<div class="post-metadata">

**Author:** ![abhisheikh\_parihar](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.aerospike.com/abhisheikh_parihar/32/1076_2.png) [@abhisheikh\_parihar](https://discuss.aerospike.com/u/abhisheikh_parihar)\
**Post date:** [April 30, 2019, 5:15pm UTC](https://discuss.aerospike.com/t/aerospike-c-client-gave-error-error-8-failed-to-resolve/6211/3 "2019-04-30T17:15:27Z")

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@Brian thanks for your response,

On same server code was working before new deployment and once we stopped the burst request it again worked

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<div class="post-metadata">

**Author:** ![Brian](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.aerospike.com/brian/32/2211_2.png) [@Brian](https://discuss.aerospike.com/u/Brian)\
**Post date:** [April 30, 2019, 5:30pm UTC](https://discuss.aerospike.com/t/aerospike-c-client-gave-error-error-8-failed-to-resolve/6211/4 "2019-04-30T17:30:23Z")

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The DNS lookup has a timeout (ClientPolicy.timeout). It’s likely that the burst in activity caused the DNS lookup to be slower thus causing a timeout.