Skip to content

Commit dd29fcb

Browse files
Merge pull request #225625 from cherylmc/ipsecfaq
updates
2 parents 265ac29 + d881c97 commit dd29fcb

File tree

4 files changed

+23
-60
lines changed

4 files changed

+23
-60
lines changed

articles/vpn-gateway/vpn-gateway-vpn-faq.md

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -6,7 +6,7 @@ author: cherylmc
66

77
ms.service: vpn-gateway
88
ms.topic: conceptual
9-
ms.date: 01/10/2023
9+
ms.date: 01/30/2023
1010
ms.author: cherylmc
1111
---
1212

includes/vpn-gateway-faq-ipsecikepolicy-include.md

Lines changed: 19 additions & 56 deletions
Original file line numberDiff line numberDiff line change
@@ -2,7 +2,7 @@
22
title: include file
33
author: cherylmc
44
ms.service: vpn-gateway
5-
ms.date: 05/25/2022
5+
ms.date: 01/30/2023
66
ms.author: cherylmc
77
---
88
### Is Custom IPsec/IKE policy supported on all Azure VPN Gateway SKUs?
@@ -19,72 +19,29 @@ No, you must specify all algorithms and parameters for both IKE (Main Mode) and
1919

2020
### What are the algorithms and key strengths supported in the custom policy?
2121

22-
The following table lists the supported cryptographic algorithms and key strengths configurable by the customers. You must select one option for every field.
23-
24-
| **IPsec/IKEv2** | **Options** |
25-
| --- | --- |
26-
| IKEv2 Encryption | GCMAES256, GCMAES128, AES256, AES192, AES128, DES3, DES |
27-
| IKEv2 Integrity | GCMAES256, GCMAES128, SHA384, SHA256, SHA1, MD5 |
28-
| DH Group | DHGroup24, ECP384, ECP256, DHGroup14 (DHGroup2048), DHGroup2, DHGroup1, None |
29-
| IPsec Encryption | GCMAES256, GCMAES192, GCMAES128, AES256, AES192, AES128, DES3, DES, None |
30-
| IPsec Integrity | GCMAES256, GCMAES192, GCMAES128, SHA256, SHA1, MD5 |
31-
| PFS Group | PFS24, ECP384, ECP256, PFS2048, PFS2, PFS1, None |
32-
| QM SA Lifetime | Seconds (integer; **min. 300**/default 27000 seconds)<br>KBytes (integer; **min. 1024**/default 102400000 KBytes) |
33-
| Traffic Selector | UsePolicyBasedTrafficSelectors ($True/$False; default $False) |
34-
| | |
35-
36-
> [!IMPORTANT]
37-
> * DHGroup2048 & PFS2048 are the same as Diffie-Hellman Group **14** in IKE and IPsec PFS. See [Diffie-Hellman Groups](#DH) for the complete mappings.
38-
> * For GCMAES algorithms, you must specify the same GCMAES algorithm and key length for both IPsec Encryption and Integrity.
39-
> * IKEv2 Main Mode SA lifetime is fixed at 28,800 seconds on the Azure VPN gateways.
40-
> * QM SA Lifetimes are optional parameters. If none was specified, default values of 27,000 seconds (7.5 hrs) and 102400000 KBytes (102GB) are used.
41-
> * UsePolicyBasedTrafficSelector is an option parameter on the connection. See the next FAQ item for "UsePolicyBasedTrafficSelectors".
42-
43-
### Does everything need to match between the Azure VPN gateway policy and my on-premises VPN device configurations?
44-
45-
Your on-premises VPN device configuration must match or contain the following algorithms and parameters that you specify on the Azure IPsec/IKE policy:
46-
47-
* IKE encryption algorithm
48-
* IKE integrity algorithm
49-
* DH Group
50-
* IPsec encryption algorithm
51-
* IPsec integrity algorithm
52-
* PFS Group
53-
* Traffic Selector (*)
54-
55-
The SA lifetimes are local specifications only, don't need to match.
56-
57-
If you enable **UsePolicyBasedTrafficSelectors**, you need to ensure your VPN device has the matching traffic selectors defined with all combinations of your on-premises network (local network gateway) prefixes to/from the Azure virtual network prefixes, instead of any-to-any. For example, if your on-premises network prefixes are 10.1.0.0/16 and 10.2.0.0/16, and your virtual network prefixes are 192.168.0.0/16 and 172.16.0.0/16, you need to specify the following traffic selectors:
58-
* 10.1.0.0/16 <====> 192.168.0.0/16
59-
* 10.1.0.0/16 <====> 172.16.0.0/16
60-
* 10.2.0.0/16 <====> 192.168.0.0/16
61-
* 10.2.0.0/16 <====> 172.16.0.0/16
22+
The following table lists the supported cryptographic algorithms and key strengths that you can configure. You must select one option for every field.
23+
24+
[!INCLUDE [Algorithm and keys table](vpn-gateway-ipsec-ike-algorithm-include.md)]
25+
26+
[!INCLUDE [Important requirements table](vpn-gateway-ipsec-ike-requirements-include.md)]
6227

6328
For more information, see [Connect multiple on-premises policy-based VPN devices](../articles/vpn-gateway/vpn-gateway-connect-multiple-policybased-rm-ps.md).
6429

6530
### <a name ="DH"></a>Which Diffie-Hellman Groups are supported?
6631

67-
The table below lists the supported Diffie-Hellman Groups for IKE (DHGroup) and IPsec (PFSGroup):
32+
The following table lists the corresponding Diffie-Hellman groups supported by the custom policy:
6833

69-
| **Diffie-Hellman Group** | **DHGroup** | **PFSGroup** | **Key length** |
70-
| --- | --- | --- | --- |
71-
| 1 | DHGroup1 | PFS1 | 768-bit MODP |
72-
| 2 | DHGroup2 | PFS2 | 1024-bit MODP |
73-
| 14 | DHGroup14<br>DHGroup2048 | PFS2048 | 2048-bit MODP |
74-
| 19 | ECP256 | ECP256 | 256-bit ECP |
75-
| 20 | ECP384 | ECP384 | 384-bit ECP |
76-
| 24 | DHGroup24 | PFS24 | 2048-bit MODP |
77-
| | | | |
34+
[!INCLUDE [Diffie-Hellman groups](vpn-gateway-ipsec-ike-diffie-hellman-include.md)]
7835

79-
For more information, see [RFC3526](https://tools.ietf.org/html/rfc3526) and [RFC5114](https://tools.ietf.org/html/rfc5114).
36+
Refer to [RFC3526](https://tools.ietf.org/html/rfc3526) and [RFC5114](https://tools.ietf.org/html/rfc5114) for more details.
8037

8138
### Does the custom policy replace the default IPsec/IKE policy sets for Azure VPN gateways?
8239

8340
Yes, once a custom policy is specified on a connection, Azure VPN gateway will only use the policy on the connection, both as IKE initiator and IKE responder.
8441

8542
### If I remove a custom IPsec/IKE policy, does the connection become unprotected?
8643

87-
No, the connection will still be protected by IPsec/IKE. Once you remove the custom policy from a connection, the Azure VPN gateway reverts back to the [default list of IPsec/IKE proposals](../articles/vpn-gateway/vpn-gateway-about-vpn-devices.md) and restart the IKE handshake again with your on-premises VPN device.
44+
No, the connection will still be protected by IPsec/IKE. Once you remove the custom policy from a connection, the Azure VPN gateway reverts back to the [default list of IPsec/IKE proposals](../articles/vpn-gateway/vpn-gateway-about-vpn-devices.md#RouteBasedOffers) and restart the IKE handshake again with your on-premises VPN device.
8845

8946
### Would adding or updating an IPsec/IKE policy disrupt my VPN connection?
9047

@@ -104,7 +61,10 @@ Yes. A VNet-to-VNet tunnel consists of two connection resources in Azure, one fo
10461

10562
### What is the default DPD timeout value? Can I specify a different DPD timeout?
10663

107-
The default DPD timeout is 45 seconds. You can specify a different DPD timeout value on each IPsec or VNet-to-VNet connection between 9 seconds to 3600 seconds.
64+
The default DPD timeout is 45 seconds. You can specify a different DPD timeout value on each IPsec or VNet-to-VNet connection, from 9 seconds to 3600 seconds.
65+
66+
> [!NOTE]
67+
> The default value is 45 seconds on Azure VPN gateways. Setting the timeout to shorter periods will cause IKE to rekey more aggressively, causing the connection to appear to be disconnected in some instances. This may not be desirable if your on-premises locations are farther away from the Azure region where the VPN gateway resides, or when the physical link condition could incur packet loss. The general recommendation is to set the timeout between **30 and 45** seconds.
10868
10969
### Does custom IPsec/IKE policy work on ExpressRoute connection?
11070

@@ -131,6 +91,9 @@ If your static routing or route based IKEv1 connection is disconnecting at routi
13191

13292
If your connection is reconnecting at random times, follow our [troubleshooting guide](../articles/vpn-gateway/vpn-gateway-troubleshoot-site-to-site-disconnected-intermittently.md).
13393

134-
### Where can I find more configuration information for IPsec?
94+
### Where can I find configuration information and steps?
95+
96+
See the following articles for more information and configuration steps.
13597

136-
See [Configure IPsec/IKE policy for S2S or VNet-to-VNet connections](../articles/vpn-gateway/vpn-gateway-ipsecikepolicy-rm-powershell.md).
98+
* [Configure IPsec/IKE policy for S2S or VNet-to-VNet connections - Azure portal](../articles/vpn-gateway/ipsec-ike-policy-howto.md)
99+
* [Configure IPsec/IKE policy for S2S or VNet-to-VNet connections - Azure PowerShell](../articles/vpn-gateway/vpn-gateway-ipsecikepolicy-rm-powershell.md)

includes/vpn-gateway-ipsec-ike-algorithm-include.md

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,7 +1,7 @@
11
---
22
author: cherylmc
33
ms.author: cherylmc
4-
ms.date: 01/11/2023
4+
ms.date: 01/30/2023
55
ms.service: vpn-gateway
66
ms.topic: include
77
---

includes/vpn-gateway-ipsec-ike-requirements-include.md

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -28,9 +28,9 @@ ms.topic: include
2828

2929
* IKE Main Mode SA lifetime is fixed at 28,800 seconds on the Azure VPN gateways.
3030

31-
* If you set **UsePolicyBasedTrafficSelectors** to $True on a connection, it will configure the Azure VPN gateway to connect to policy-based VPN firewall on premises. If you enable PolicyBasedTrafficSelectors, you need to ensure your VPN device has the matching traffic selectors defined with all combinations of your on-premises network (local network gateway) prefixes to/from the Azure virtual network prefixes, instead of any-to-any.
31+
* 'UsePolicyBasedTrafficSelectors' is an optional parameter on the connection. If you set **UsePolicyBasedTrafficSelectors** to $True on a connection, it will configure the Azure VPN gateway to connect to policy-based VPN firewall on premises. If you enable PolicyBasedTrafficSelectors, you need to ensure your VPN device has the matching traffic selectors defined with all combinations of your on-premises network (local network gateway) prefixes to/from the Azure virtual network prefixes, instead of any-to-any.
3232

33-
For example, if your on-premises network prefixes are 10.1.0.0/16 and 10.2.0.0/16, and your virtual network prefixes are 192.168.0.0/16 and 172.16.0.0/16, you need to specify the following traffic selectors:
33+
For example, if your on-premises network prefixes are 10.1.0.0/16 and 10.2.0.0/16, and your virtual network prefixes are 192.168.0.0/16 and 172.16.0.0/16, you need to specify the following traffic selectors:
3434

3535
* 10.1.0.0/16 <====> 192.168.0.0/16
3636
* 10.1.0.0/16 <====> 172.16.0.0/16

0 commit comments

Comments
 (0)