Effects
Reaching either the ingress or egress limit on a storage account can have severe impact on your applications. If your VMs use unmanaged disks in a storage account at the limit, you may see increased latency for disk operations. Any queues, tables, shared files, or blobs in the storage account will see degraded performance if you exceed the performance targets set by Azure.
Ingress Limit
The ingress limit restricts the rate at which data can be sent to a storage account. Storage account ingress limits range from 5 Gbps to 25 Gbps depending on region and replication configuration. If the ingress limit is reached on a storage account, your application will likely see increased latency for requests to the storage account, which can include writes to unmanaged disks, shared files, queued messages, and table updates.
Since the ingress limit is managed per storage account, you can achieve higher throughput by using additional storage accounts. For Standard storage accounts, you can also request a limit increase with Azure Support.
Egress Limit
The egress limit restricts the rate at which data can be read from a storage account. Storage account egress limits range from 10 Gbps to 30 Gbps for v1 storage accounts, and are set at 50 Gbps for v2 storage accounts. If you are hitting the egress limit for your storage account, look into whether a CDN could be used to reduce the number of requests going to your storage account. Another option is to use multiple storage accounts and split up your resources between them to achieve higher total throughput.
The Azure documentation does not say you can increase a limit increase for v2 storage accounts, but you can still open a support ticket to request a limit increase and discuss options for working around the egress limit with Azure support.
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